Garnet - January
Hardness: 6,5 to 7,5
Colour: Mostly dark red
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Garnet is a group of minerals that have been used since the Bronze Age as gemstones and abrasives. Garnets are most often seen in red, but are available in a wide variety of colors spanning the entire spectrum. The name "garnet" comes from the Latin granatus ("grain"), possibly a reference to the Punica granatum ("pomegranate"), a plant with red seeds similar in shape, size, and color to some garnet crystals.
In the greek mythologies pomegranate was seen as a symbol of love and usually associated with eternity.
Amethyst - February
Hardness: 7
Colour:Violet
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Amethyst is a purple variety of quartz often used as an ornament. The name comes from the Greek a ("not") and methuskein ("to intoxicate"), a reference to the belief that the stone protected its owner from drunkenness; the ancient Greeks and Romans wore amethyst and made drinking vessels of it in the belief that it would prevent intoxication. Supposedly, when a drunken Dionysus was pursuing a maiden called Amethystos, who refused his affections, she prayed to the gods to remain chaste. The goddess Artemis granted the prayer, transforming her into a white stone; humbled by Amethystos' desire to remain chaste, Dionysus poured wine over the stone she had become as an offering, dying the crystals purple. Variants of the story include that Dionysus, the god of intoxication, had been insulted by a mortal and swore revenge on the next mortal who crossed his path, creating fierce tigers to carry out his wish; the mortal turned out to be a beautiful young woman, Amethystos, who was on her way to pay tribute to Artemis. Her life is spared by Artemis, who transforms the maiden into a statue of pure crystalline quartz to protect her from the brutal claws. Dionysus wept tears of wine in remorse for his action at the sight of the beautiful statue. The god's tears stained the quartz purple.Another variation involves the goddess Rhea presenting Dionysus with the amethyst stone to preserve the winedrinker's sanity
It is also a symbol of heavenly understanding, and of the pioneer in thought and action on the philosophical, religious, spiritual, and material planes. Ranking members of the Roman Catholic Church traditionally wear rings set with a large amethyst as part of their office.
Amethyst occurs in a continuum of primary hues from a light slightly pinkish violet to a deep grape purple. Amethyst may exhibit one or both secondary hues, red and/or blue. The ideal grade is called "Deep Siberian" and has a primary purple hue of around 75 - 80 percent, 15-20 percent blue and (depending on the light source) red secondary hues
 Amethyst occurs at many localities in the United States, but these specimens are rarely fine enough for use in jewelry. Among these may be mentioned Amethyst Mountain, Texas; Yellowstone National Park; Delaware County, Pennsylvania; Haywood County, North Carolina; and Deer Hill and Stow, Maine. It is found also in the Lake Superior region. Amethyst is relatively common in northwestern Ontario, and in various locations throughout Nova Scotia, but uncommon elsewhere in Canada. Amethyst is produced in abundance from the state of Minas Gerais in Brazil where it occurs in large geodes within volcanic rocks.Amethyst was used as a gemstone by the ancient Egyptians and was largely employed in antiquity for intaglios. Beads of amethyst are found in Anglo-Saxon graves in England. It is a widely distributed mineral, but fine, clear specimens that are suitable for cutting as ornamental stones are confined to comparatively few localities. Such crystals occur either in the cavities of mineral-veins and in granitic rocks, or as a lining in agate geodes. A huge geode, or "amethyst-grotto," from near Santa Cruz in southern Brazil was exhibited at the Düsseldorf, Germany Exhibition of 1902. Many of the hollow agates of Brazil and Uruguay contain a crop of amethyst crystals in the interior. Much fine amethyst comes from Russia, especially from near Mursinka in the Ekaterinburg district, where it occurs in drusy cavities in granitic rocks. Many localities in India yield amethyst.
Aquamarine - March
Hardness: 7.5 - 8
Colour: light blue
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Aquamarine (Lat. aqua marina, "water of the sea") is a gemstone-quality transparent variety of beryl, having a delicate blue or turquoise color, suggestive of the tint of seawater. It's closely related to the gem emerald.
It occurs at most localities which yield ordinary beryl, some of the finest coming from Russia. The gem-gravel placer deposits of Sri Lanka contain aquamarine. Clear yellow beryl, such as occurs in Brazil, is sometimes called aquamarine chrysolite. Zambia also produces nice aquamarine as well as USA, Brazil, Madagascar, Malawi, Tanzania and Kenya. Much of today's aquamarine is heated to give it a better color blue. The deeper the blue color, the more valuable the gem is considered.
The biggest aquamarine ever mined was found at the city of Marambaia, Minas Gerais, Brazil, in 1910. It weighed over 110 kg, and its dimensions were 48.5 cm long and 42 cm in diameter.
Aquamarine is the official state gem of Colorado.
People in the Middle Ages thought that aquamarine could magically overcome the effects of poison.
Diamond - April
For more information about diamonds, please check "Diamond Info"in this site.
Emerald - May
Hardness: 7,5 to 8
Colour: green
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Emeralds are highly included, so the brittleness (resistance to breakage) is classified as generally poor. The origin of the word "Emerald" is said to be a Sanskrit word meaning "green". Emeralds come in many shades of green and bluish green. There is a wide spectrum of clarity, dependent on the inclusions and fractures in the crystal. Clear stones with dark yet vibrant color command the highest prices.
Most emeralds are oiled as part of the post lapidary process, in order to improve their clarity. Cedar oil is often used, having a similar refractive index, and it is a generally accepted practice.
Emeralds in antiquity were mined by the Egyptians and in Austria, as well as Swat in northern Pakistan.
A rare type of emerald known as a trapiche emerald is occasionally found in the mines of Colombia. A trapiche emerald exhibits a "star" pattern; it has raylike spokes of dark carbon impurities that give the emerald a six-pointed radial pattern. It is named for the trapiche, a grinding wheel used to process sugarcane in the region. Colombian emeralds are generally the most prized due to their transparency and fire. Some of the most rare emeralds come from three main emerald mining areas in Colombia: Muzo, Coscuez, and Chivor. Fine emeralds are also found in other countries, such as Zambia, Brazil, Zimbabwe, Madagascar, Pakisan, India, Afghanistan and Russia.
The value of an emerald depends on cut, color, clarity, and carat. The characteristics of Colombian emeralds set the highest standards of quality
Alexandrite - June
Hardness: 9
Colour: variable
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The alexandrite displays a color change (alexandrite effect) dependent upon light, along with strong pleochroism. Alexandrite results from small scale replacement of aluminium by chromium oxide, which is responsible for alexandrite's characteristic green to red color change. Alexandrite from the Ural Mountains in Russia is green by daylight and red by incandescent light. Other varieties of alexandrite may be yellowish or pink in daylight and a columbine or raspberry red by incandescent light. The optimum or "ideal" color change would be fine emerald green to fine purplish red, but this is exceedingly rare. Because of their rarity and the color change capability, "ideal" alexandrite gems are some of the most expensive in the world.
According to a widely popular but controversial story, alexandrite was discovered by the Finnish mineralogist Nils Gustaf Nordenskiöld, (1792 -1866) on the tsarevitch Alexanders sixteenth birthday on April 17, 1834 and named alexandrite in honor of the future Tsar Alexander II of Russia. Sometimes, Nils Gustaf Nordenskiöld is confused with his son, Adolf Erik Nordenskjöld (1832–1901), also a famous Finnish geologist, mineralogist and arctic explorer who accompanied his father to the Ural Mountains to study the iron and copper mines at Tagilsk in 1853. However, Adolf Erik Nordenskjöld was only two years old when Alexandrite was discovered and only ten years old when a description of the stone was published under the name of Alexandrite for the first time.
Although it was Nordenskjold who discovered alexandrite, he could not possibly have discovered and named it on Alexander's birthday. Nordensljold's initial discovery occurred as a result of an examination of a newly found mineral sample he had received from Perovskii, which he identified as emerald at first. After the discovery of emeralds in the roots of an upturned tree, the first emerald mine had been opened in 1831, not long before Nordensjold had received this particular sample. Confused with the high hardness however, he decided to continue his examinations. Later that evening, while looking at the specimen under candlelight, he was surprised to see that the color of the stone had changed to raspberry-red instead of green. Later, he confirmed the discovery of a new variety of chrysoberyl, and suggested the name "diaphanite"(from the Greek "di" two and "aphanes", unseen or "phan", to appear, or show).
 The name of the first person to actually find this stone has been lost in the mists of time. However, the first person to bring it to public attention, and ensure that it would be forever associated with the Imperial family was Count Lev Alekseevich Perovskii (1792-1856.)
The finest alexandrites were found in the Ural Mountains, the largest cut stones being in the 30 carat (6 g) range, though many fine examples have been discovered in Sri Lanka (up to 65 cts.), India (Andhra Pradesh), Brazil, Myanmar, and especially Zimbabwe (small stones usually under 1 carat (200 mg) but with intense color change). Overall, stones from any locale over 5 carats (1 g) would be considered extremely rare, especially gems with fine color change. Alexandrite is both hard and tough, making it very well suited to wear in jewelry.
The gem has given rise to the adjective "alexandritic", meaning any transparent gem or material which shows a noted change in color between natural and incandescent light. Some other gem varieties of which alexandritic specimens have been found include sapphire, garnet, and spinel.
Ruby - July
Ruby is a red gemstone that varies from a light pink to a blood red, a variety of the mineral corundum (aluminium oxide). The color is caused mainly by chromium. Its name comes from ruber, Latin for red. Other varieties of gem-quality corundum are called sapphires. It is considered one of the four precious stones, together with the sapphire, the emerald and the diamond.
Rubies are mined in Africa, Asia, Australia, Greenland, Madagascar and North Carolina. They are most often found in Myanmar (Burma), Sri Lanka, Kenya, Madagascar, and Cambodia, but they have also been found in the U.S. states of Montana, North Carolina and South Carolina. The Mogok Valley in Upper Myanmar has produced some of the finest rubies but, in recent years, very few good rubies have been found there. The unique color in Myanmar (Burmese) rubies is described as "pigeon’s blood". They are known in the trade as “Mogok” rubies. In central Myanmar the area of Mong Hsu also produces rubies. The latest ruby deposit to be found in Myanmar is situated in Nam Ya. In 2002 rubies were found in the Waseges River area of Kenya. Sometimes spinels are found along with rubies in the same rocks and are mistaken for rubies. However, fine red spinels may approach the average ruby in value.
 All natural rubies have imperfections in them, including color impurities and inclusions of rutile needles known as "silk". Gemologists use these needle inclusions found in natural rubies to distinguish them from synthetics, stimulants, or substitutes. Usually the rough stone is heated before cutting. Almost all rubies today are treated in some form (of which heat treatment is the most common practice), and rubies which are completely untreated and still of excellent quality command a large premium. In general we can list the following types of improvements: color alteration, improving transparency by dissolving rutile inclusions, healing of fractures (cracks) or even completely filling them.
Prices of rubies are primarily determined by colour (the brightest and best "red" called Pigeon Blood Red, command a huge premium over other Rubies of similar quality). After Colour follows clarity: similar to Diamonds, a clear stone will command a premium, but a Ruby without any needle-like rutile inclusions will indicate the stone has been treated one way or another. Cut and Carat (size) also determine the price approximately like clarity does.
Sometimes rubies show a 3-point or 6-point star. These Rubies are cut into cabochons to display the effect properly. Stars are best visible with a single-light source, and move across the stone as the light moves. Such effects are called asterism and occur when light is reflected off the silk (the rutile inclusions) in a certain way. This is one example where inclusions actually increase the value of a gemstone. Rubies can furthermore show color changes — though this occurs very rarely — and chatoyancy.
Peridot - August
Hardness: 6,5 - 7,0
Colour: olive green
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Peridot is the gem quality variety of forsteritic olivine. The name of the gemstone is believed to come from either the Arabic word faridat meaning "gem" or the French word peritot meaning "unclear." Peridot is one of the few gemstones that comes in only one colour. The depth of green depends on how much iron is contained in the crystal structure, and varies from yellow-green to olive to brownish green. Peridot is also often referred to as "poor man's emerald". Olivine is a very abundant mineral, but gem-quality peridot is rather rare. Peridot crystals have been collected from iron-nickel meteorites
Sapphire - September
Sapphire (from Hebrew: Sapir) is the single-crystal form of aluminium oxide (Al2O3), a mineral known as corundum. It can be found naturally as gemstones or manufactured in large crystal boules for varied applications, including infrared optical components, watch faces, high-durability windows, and wafers for the deposition of semiconductors such as GaN nanorods.
The corundum group consists of pure aluminium oxide. Trace amounts of other elements such as iron, titanium and chromium give sapphires their blue, yellow, pink, purple, orange or greenish color. Sapphire includes any gemstone quality varieties of the mineral corundum except the fully saturated red variety, which is instead known as ruby.
Although blue is considered the normal color for sapphire, it is found in the full range of spectral colors as well as brown, colorless, grey and black. Those other than blue in color are considered fancy color sapphires.
 According to Rebbenu Bachya, and many English Bible translations, the word Sapir in the verse Exodus 28:18 means Sapphire and was the stone on the Ephod representing the tribe of Issachar. However, this is extremely disputed as though it is true that the english word sapphire derives from the Hebrew sapir (via Greek sapphiros), Sapphires were actually not really known about before the Roman Empire (and were initially considered to be forms of jacinth, rather than deserving of a word to themselves), and prior to that time sapphiros referred to blue gems in general. It is thought by scholars that the sapphire of the Bible was actually lapis lazuli - which was frequently sent as a gift between middle-eastern nations in Biblical times (Texas Natural Science Center, 2006). There is a wide range of views among traditional sources about which tribe the stone refers to. Supernatural powers were attributed to gems in India. One way this was manifested was the interdependence between gems and planets. Ruby, associated with the Sun, was the Lord of Gems, for the Sun lorded over all the planets. Blue sapphire is associated with Saturn (Wojtilla, 1973), yellow sapphire with Jupiter.
Opal - October
Hardness: 6
Colour: Variable |
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Opal ranges from clear through white, gray, red, yellow, green, shore, blue, magenta, brown, and black. Of these hues, red and black are the most rare and dear, whereas white and green are the most common; these are a function of growth size into the red and infrared wavelengths. Common opal is truly amorphous, but precious opal does have a structural element. The word opal comes from the Latin opalus, by Greek òpalliòs, by Sanskrit upálá[s] for "stone", originally a millstone with upárá[s] for slab. Opals are also Australia's national gemstone. Opal is a mineraloid gel which is deposited at relatively low temperature and may occur in the fissures of almost any kind of rock, being most commonly found with limonite, sandstone, rhyolite, and basalt.
Opal is one of the mineraloids that can form or replace fossils. The resulting fossils, though not of any extra scientific interest, appeal to collectors.
In the middle ages, opal was considered a stone that could provide great luck because it was believed to possess all the virtues of each gemstone whose color was represented in the color spectrum of the opal. Even under the last czar at the beginning of the 20th century, it was believed that when a Russian of any sex, of any rank, saw an opal, amongst other goods offered for sale, he or she would not buy anything more, since, in the judgement of subjects of the czar, the opal embodied the evil eye.
Topaz - November
Hardness: 8
Colour: Variable
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Topaz is transparent but is usually tinted by impurities; typical topaz is wine or straw-yellow. They may also be white, gray, green, blue, pink or reddish-yellow and transparent or translucent. When heated, yellow topaz often becomes reddish-pink. Topaz can also be irradiated, turning the stone blue, ranging from a light pure color to very dark almost electric blue. A recent trend in jewelry is the manufacture of topaz specimens that display iridescent colors, by applying a thin layer of titanium oxide via physical vapor deposition, this stone is then sold as 'mystic topaz'.
Topaz is commonly associated with silicic igneous rocks of the granite and rhyolite type. It typically crystallizes in granitic pegmatites or in vapor cavities in rhyolite lava flows like those at Topaz Mountain in western Utah. It may be found with fluorite and cassiterite. It can be found in the Ural and Ilmen mountains, Afghanistan, Czech Republic, Germany, Norway, Pakistan, Italy, Sweden, Japan, Brazil, Mexico, and the United States.
Topaz crystals from Brazilian pegmatites are up to 80cm x 60cm x 60cm in size. The biggest topaz crystal ever found, named "El Dorado", was found in Brazil in 1984. It weighs 6.2 kg and belongs to the British Royal Collection.
Topaaz Blauwe Topaaz
The name "topaz" is derived from the Greek tòpazi[òs], which was the name of an island in the Red Sea that was difficult to find and from which a yellow stone (now believed to be chrysolite: yellowish olivine) was mined in ancient times; topaz itself (rather than topazios) wasn't really known about before the classical era. In the Middle Ages the name topaz was used to refer to any yellow gemstone, but now the name is only properly applied to the silicate described above.
Many modern English translations of the Bible, including the King James Version mention topaz in the bible book of exodus 28:17: And thou shalt set in it settings of stones, even four rows of stones: the first row shall be a sardius, a topaz, and a carbuncle: this shall be the first row. in reference to a stone in the Hoshen. However, since these translations as topaz all derive from the Septuagint translation tòpazi[òs], which as mentioned above referred to a yellow stone that wasn't topaz, probably chrysolite, it should be borne in mind that topaz is not meant here. The masoretic text (the Hebrew on which most modern bible translations of the Old Testament are based) has pitdah as the gem the stone is made from; pitdah is of unknown meaning, though scholars think it is related to an Assyrian word meaning flashed.
Turquoise - December
Hardness: 5 tot 6
Colour: blue to green
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Turquoise is an opaque, blue-to-green mineral. It is rare and valuable in finer grades and has been prized as a gem and ornamental stone for thousands of years owing to its unique hue. In recent times turquoise, like most other opaque gems, has been devalued by the introduction of treatments, imitations, and synthetics onto the market, some difficult to detect even by experts.
The substance has been known by many names, but the word turquoise was derived around 16th century from the French language either from the word for Turkish (Turquois) or dark-blue stone (pierre turquin). This may have arisen from a misconception: turquoise does not occur in Turkey but was traded at Turkish bazaars by armenians to Venetian merchants who brought it to Europe. The colour, however, has been employed extensively in the decorative tiles adorning Turkish places of worship and homes for hundreds of years, beginning with the Seljuks, and the association quite possibly has caused the name to take root..
 Turquoise was among the first gems to be mined, and while many historic sites have been depleted, some are still worked to this day. These are all small-scale, often seasonal operations, owing to the limited scope and remoteness of the deposits. Most are worked by hand with little or no mechanization. However, turquoise is often recovered as a byproduct of large-scale copper mining operations, especially in the USA
Iran
For at least 2,000 years, the region once known as Persia, has remained the most important source of turquoise, for it is here that fine material is most consistently recovered. This "perfect colour" deposit, which is blue naturally, turns green when heated because getting dehyrated is restricted to a mine-riddled in Neyshabur, the 2,012-metre mountain peak of Ali-mersai, which is tens of kilometers from Mashhad, the capital of Khorasan province, Iran. A weathered and broken trachyte is host to the turquoise, which is found both in situ between layers of limonite and sandstone, and amongst the scree at the mountain's base. These workings, together with those of the Sinai Peninsula, are the oldest known.
Iranian turquoise is often found replacing feldspar. Although it is commonly marred by whitish patches, its colour and hardness are considered superior to the production of other localities. Iranian turquoise has been mined and traded abroad for centuries, and was probably the source of the first material to reach Europe.
Sinai
Since at least the First Dynasty (3000 BCE), and possibly before then, turquoise was used by the Egyptians and was mined by them in the Sinai Peninsula, called "Country of Turquoise" by the native Monitu. There are six mines in the region, all on the southwest coast of the peninsula, covering an area of some 650 km². The two most important of these mines, from a historic perspective, are Serabit el-Khadim and Wadi Maghareh, believed to be among the oldest of known mines. The former mine is situated about 4 kilometres from an ancient temple dedicated to Hathor.
The turquoise is found in sandstone that is, or was originally, overlain by basalt. Copper and iron workings are present in the area. Large-scale turquoise mining is not profitable today, but the deposits are sporadically quarried by Bedouin peoples using homemade gunpowder. In the rainy winter months, miners face a risk from flash flooding; even in the dry season, death from the collapse of the haphazardly exploited sandstone mine walls is not unheard of. The colour of Sinai material is typically greener than Iranian material, but is thought to be stable and fairly durable. Often referred to as Egyptian turquoise, Sinai material is typically the most translucent, and under magnification its surface structure is revealed to be peppered with dark blue discs not seen in material from other localities.
In proximity to nearby Eilat, Israel, an attractive intergrowth of turquoise, malachite, and chrysocolla is found. This rock is called Eilat stone and is often referred to as Israel's national stone: it is worked by local artisans for sale to tourists.
Other precious stones
Tanzanite
Hardness: 6,5
Colour: blue-violet, brown, green
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Tanzanite is an extraordinary gemstone. It occurs in only one place worldwide. Its blue, surrounded by a fine hint of purple, is a wonderful colour. It is named after the East African state of Tanzania, the only place in the world where it has been found. On its discovery in 1967, it was enthusiastically celebrated by the specialists as the 'gemstone of the 20th century'. They held their breath in excitement as they caught sight of the first deep-blue crystals which had been found in the Merelani Hills near Arusha in the north of Tanzania.
Citrine
Also called citrine quartz or citrine topaz, is an amber-colored gemstone. It is a form of quartz with ferric iron impurities, and is rarely found naturally. Most commercial citrine is in fact artificially heated amethyst or smoky quartz. Brazil is the leading producer of naturally mined citrine, with much of its production coming from the state of Rio Grande do Sul.
Zircon
Zircon is a mineral belonging to the group of nesosilicates. The natural color of zircon varies between colorless, yellow-golden, red, brown, and green. Colorless specimens that show gem quality are a popular substitute for diamond; these specimens are also known as "Matura diamond". It is not to be confused with cubic zirconia, a synthetic substance with a completely different chemical composition.
The name derives from the Arabic word zarqun, meaning vermilion, or perhaps from the Persian zargun, meaning golden-colored. These words are corrupted into "jargoon", a term applied to light-colored zircons. Yellow zircon is called hyacinth, from a word of East Indian origin; in the Middle Ages all yellow stones of East Indian origin were called hyacinth, but today this term is restricted to the yellow zircons.
Lapis Lazuli
Lapis lazuli, also known as just lapis, is a stone with one of the longest traditions of being considered a gem, with a history stretching back to 7000 BC in Mehrgarh in the Indian subcontinent, situated in between modern day Afghanistan, and Pakistan. Deep blue in color and opaque, this gemstone was highly prized by the pharaohs of ancient Egypt, as can be seen by its prominent use in many of the treasures recovered from pharaonic tombs. It is still extremely popular today.
Lapis is a rock and not a mineral because it is made up from various other minerals. To be a mineral it would have one constituent only.
The first part of the name is the Latin lapis, meaning stone. The second part, lazuli, is the genitive form of the medieval Latin lazulum, which came from Arabic (al-)lazward, which came from Persian lazhward, which came from Sanskrit Raja Warta meaning Ring/Life of the King. This was originally a place-name, but soon came to mean blue because of its association with the stone. The English word azure, the Spanish and Portuguese azul, and the Italian azzurro are cognates. Taken as a whole, lapis lazuli means "stone of azure".
The finest color is intense blue, lightly dusted with small flecks of golden pyrite. There should be no white calcite veins and the pyrite inclusions should be small. Stones that contain too much calcite or pyrite are not as valuable. Patches of pyrite are an important help in identifying the stone as genuine and do not detract from its value. Often, inferior lapis is dyed to improve its color, but this is often a very dark blue with a noticeable grey cast.
The finest lapis comes from the Badakshan area of Afghanistan. Shortugai, an Indus Valley Civilization site on the Oxus river in northern Afghanistan, was a mining centre for lapis lazuli. This source of lapis may be the oldest continually worked set of mines in the world, the same mines operating today having supplied the lapis of the pharaohs and ancient Sumerians. Using this ancient source, the Indus Valley Civilization's artists used to make beautiful carvings and traders used to trade them to distant places. In addition to the Afghan deposits, lapis has been found in the Andes near Ovalle, Chile, where it is usually pale rather than deep blue. Other less important sources are the Lake Baikal region of Russia, Siberia, Angola, Burma, Pakistan, USA (California and Colorado), Canada and India.
Lapis takes an excellent polish and has been made into jewellery, carvings, boxes, mosaics, ornaments and vases. In architecture it has been used for cladding the walls and columns of palaces and churches.
It was also ground and processed to make the pigment Ultramarine for tempera paint and, more rarely, oil paint. Its usage as a pigment in oil paint ended in the early 19th century as a chemically identical synthetic variety, often called French Ultramarine, became available. In ancient Egypt lapis lazuli was a favorite stone for amulets and ornaments such as scarabs; it was also used by the Assyrians and Babylonians for seals. Egyptian burial sites dating before 3000 B.C. contained thousands of jewellery items, many of lapis. Powdered lapis was used by Egyptian ladies as a cosmetic eye shadow.
As inscribed in the 140th chapter of the Egyptian Book of the Dead, lapis lazuli, in the shape of an eye set in gold, was considered an amulet of great power. On the last day of the month, an offering was made before this symbolic eye, for it was believed that, on that day, the supreme being placed such an image on his head.
The ancient royal Sumerian tombs of Ur, located near the Euphrates River in lower Iraq, contained more than 6000 beautifully executed lapis lazuli statuettes of birds, deer, and rodents as well as dishes, beads, and cylinder seals. These carved artifacts undoubtedly came from material mined in Badakhshan in northern Afghanistan. The word lazuli itself originates from the Persian dialect of Badakhshan. Much Sumerian and Akkadian poetry makes reference to lapis lazuli as a gem befitting royal splendor.
In ancient times, lapis lazuli was known as sapphire,[citation needed] which is the name that is used today for the blue corundum variety sapphire. It appears to have been the sapphire of ancient writers because Pliny refers to sapphirus as a stone sprinkled with specks of gold. A similar reference can be found in the Hebrew Bible in Job 28:6.
The Romans believed that lapis was a powerful aphrodisiac. In the Middle Ages, it was thought to keep the limbs healthy, and free the soul from error, envy and fear.
It was once believed that lapis had medicinal properties. It was ground down, mixed with milk and applied as a dressing for boils and ulcers.
Many of the blues in painting from medieval Illuminated manuscripts to Renaissance panels were derived from lapis lazuli. Ground to a powder and processed to remove impurities and isolate the component lazurite, it forms the pigment ultramarine. This clear, bright blue, which was one of the few available to painters before the 19th century, cost a princely sum. As tempera painting was superseded by the advent of oil paint in the Renaissance, painters found that the brilliance of ultramarine was greatly diminished when it was ground in oil and this, along with its cost, led to a steady decline in usage. Since the synthetic version of ultramarine was discovered in the 19th century (along with other 19th century blues, such as cobalt blue), production and use of the natural variety has almost ceased, though several pigment companies still produce it and some painters are still attracted to its brilliance and its romantic history.
Kunziet
Kunzite is a pink to lilac colored gemstone, a variety of spodumene with the colour coming from minor to trace amounts of manganese. Some (but not all) kunzite used for gemstones has been heated to enhance its colour. It was named in honor of New York mineralogist and gemologist George Frederick Kunz. It has been found in Brazil, USA, Canada, CIS, Mexico, Sweden, Western Australia, Afghanistan and Pakistan
Moonstone
The most common moonstone is of the mineral Adularia. The Plagioclase Feldspar Oligoclase also produces moonstone specimens. The sheen is caused by light reflecting internally in the moonstone from layer inclusions of different Feldspars.
Pearl
A pearl is a hard, rounded object produced by certain animals, primarily mollusks such as pearl oysters. Pearls can be used in jewelry and also crushed in cosmetics or paint formulations. Pearl is valued as a gemstone and is cultivated or harvested for jewelry. The unique luster of pearls depends upon the reflection and refraction of light from the translucent layers and is finer in proportion as the layers become thinner and more numerous. The iridescence that some pearls display is caused by the overlapping of successive layers, which breaks up light falling on the surface. Pearls are often white, but come naturally in nearly every color. Pearls are often dyed yellow, green, blue, brown, purple, or black.
The difference between natural and cultured pearls focuses on whether the pearl was created by nature, without human intervention, or with human aid. Pearls are formed inside the shell of certain bivalve mollusks. As a response to an irritant inside its shell, the mollusk will deposit layers of calcium carbonate (CaCO3) in the form of the minerals aragonite or calcite (both crystalline forms of calcium carbonate) held together by an organic horn-like compound called conchiolin.This combination of calcium carbonate and conchiolin is called nacre, or as most know it, mother-of-pearl. The commonly held belief that a grain of sand acts as the irritant is in fact rarely the case. Typical stimuli include organic material, parasites, or even damage that displaces mantle tissue to another part of the animal's body. These small particles or organisms enter the animal when the shell valves are open for feeding or respiration. In cultured pearls, the irritant is typically a cut piece of the mantle epithelium, together with processed shell beads, the combination of which the animal accepts into its body.
Quality natural pearls are very rare jewels. Actual value of a natural pearl is determined as other "precious" gems. Valuation factors include size, shape and quality of surface, orient, and luster.
Single natural pearls are often sold as a collector item, or set as a centerpieces in unique jewelry. Very few matched strands of natural pearls exist, and those that do often sell for hundreds of thousands of dollars. Yachtsman and financier Cartier purchased the landmark Cartier store on Fifth Avenue in New York for $100 cash and a double strand of matched natural pearls valued at $1 million.
Keshi pearls, although they often occur by chance, are not considered natural pearls. They are a byproduct of the culturing process, and hence do not happen without human intervention. These pearls are quite small: typically a few millimeters in size. Keshi pearls are produced by many different types of marine mollusks and freshwater mussels in China. Today many "keshi" pearls are actually intentional, with post-harvest shells returned to the water to regenerate a pearl in the existing pearl sac.
Previously natural pearls were found in many parts of the world. Present day natural pearling is confined mostly to seas off Bahrain. Australia also has one of the world's last remaining fleets of pearl diving ships. Australian pearl divers dive for south sea pearl oysters to be used in the cultured south sea pearl industry. The catch of pearl oysters is similar to the numbers of oysters taken during the natural pearl days. Hence significant numbers of natural pearls are still found in the Australian Indian Ocean waters from wild oysters. X-Ray examination is required to positively verify natural pearls found today.
Jade
The English word 'jade' is derived from the Spanish term piedra de ijada (first recorded in 1565) or 'loin stone', from its reputed efficacy in curing ailments of the loins and kidneys. 'Nephrite' is derived from lapis nephriticus, the Latin version of the Spanish piedra de ijada.
Nephrite and jadeite were used by people from the prehistoric for similar purposes. Both are about the same hardness as quartz, and they are exceptionally tough. They are beautifully coloured and can be delicately shaped. Thus it was not until the 19th century that a French mineralogist determined that "jade" was in fact two different materials.
Among the earliest known jade artifacts excavated from prehistoric sites are simple ornaments such as rounded beads, buttons, and tubular jades. Additionally, jade was used for axe heads, knives, and other weapons. As metal-working technologies became available, the beauty of jade made it valuable for ornaments and decorative objects. Jade has a Mohs hardness of between 6.5 and 7.0, so it can be worked with quartz or garnet sand, and polished with bamboo or even ground jade.
Nephrite can be found in a creamy white form (known in China as "mutton fat" jade) as well as in a variety of green colours, whereas jadeitite shows more colour variations, including dazzling blue, lavender-mauve, pink, and emerald-green colours. Of the two, jadeite is rarer, documented in fewer than 12 places worldwide. Translucent emerald-green jadeitite is the most prized variety, both now and historically. As "quetzal" jade, bright green jadeitite from Guatemala was treasured by Mesoamerican cultures, and as "kingfisher" jade, vivid green rocks from Burma became the preferred stone of post-1800 Chinese imperial scholars and rulers. Burma (Myanmar) and Guatemala are the principal sources of modern gem jadeitite, and Canada of modern lapidary nephrite. Nephrite jade was used mostly in pre-1800 China as well as in New Zealand, the Pacific Coast and Atlantic Coasts of North America, Neolithic Europe, and south-east Asia. In addition to Mesoamerica, jadeitite was used by Neolithic Japanese and European cultures.
Jade is the official gemstone of British Columbia, where it is found in large deposits in the Lillooet and Cassiar regions. It is also the official gemstone of the state of Alaska, found particularly in the Kobuk area. A two ton block of jade sits outside the Anchorage Visitor’s Center in downtown Anchorage, Alaska, mined from near Kobuk and donated to the city as a showpiece.
Other gemstones
Hematiet
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Barnsteen
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Carneool
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Onyx
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Azoeriet
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Malakiet
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