Gemstones have been around for millennia, but the record shows that as far back as 3000 years ago, in India and Babylon, they believed to have descended from the heavens with magical properties able to influence both human and nature. The only way to classify gems at that time was by using color, as chemistry would not be invented until the middle ages.
Flavius Josephus, the Jewish-turned-Roman-historian, is often mentioned as having connected the 12 birthstones with the 12 gemstones mounted the Breastplate of the High Priest, and later, the 12 Foundation Stones for the New Jerusalem in the book of Revelation. But a closer examination of even just the surface details easily reveals that not only are they dissimilar, but complete opposites in purpose or intent. Historical records indeed trace multiple modifications and efforts to merge Biblical sources with non-Biblical practices, especially for Western cultures. This bothered astrologers, who insisted that birthstones be based on the motions or positions of the sun, moon, stars, and other planets. Cultures that base their list on tropical (Sun-based) or sidereal (Moon/star-based) zodiac refute the present list of accepted birthstones as just a marketing strategy to boost sales. The ancient system of birthstones states that a zodiac sign is controlled by a planet, which in turn governs each gemstone according to color (curiously only the rare and beautiful specimens). There really is no universal worldwide standard at this moment in time, but rather each culture (Indian, Tibetan, Eastern European, Western European, USA, UK, etc ) has its own list of birthstones.
Each birthstone has its own distinctive color, and features. A birthstone's natural untreated color was for centuries the only category believed to release the power native to each stone. The color tells the story of a birthstone's life, the arrangement of its atoms, the minerals, the pressures, heating and cooling, weathering, and such.
Aside from physical qualities, birthstones also have perceived qualities that have added to the lore of gemstones through the years. Some stones were believed to aid in delivering babies. Some talismans and amulets are used to protect from evil events and spirits. While others are said to induce sleep, soothe pain, prevent and and treat illness. Ancient lapidaries recorded lists and charts of which gemstones were for what purposes. For example, stones like jasper, hematite, carnelian were each found to have a different effect on certain parts of the body. There are even some beliefs that these gems could give someone incredible strength, the ability to become invisible, help foretell the future, attract wealth, and secure awards and recognitions.
The birthstone for January is a Garnet usually Pyrope.
Pyrope is the iron magnesium and aluminum silicate of the pyrope-almandine series in the Pyralspite group of the Garnet family. Its beautiful deep-red gem quality makes it one of the most popular. Pure pyrope is colorless, but its red color, sometimes very bright, is due to small quantities of chrome in the crystal structure.
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The birthstone for Febuary is Amethyst
Amethyst is the most coveted stone in the quartz group, and it is sometimes confused with beryl. It is usually found layered with milky quartz, and its color varies from purple to violet. - See more at:
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The birthstone for March is Aquamarine
Aquamarine is a form Beryl that is similar in color to sea water. So it varies from green to blue just like the oceans. Most if not all Aquamarine has been heat treated to improve or lighten the color.
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The birthstone for April is Diamond
Diamond is the only gem material comprised of a single chemical element: pure carbon, like graphite. But the atoms in diamond have been forced into a compact, three-dimensional structure by the high pressures in the upper mantle, where it is formed.
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The birthstone for May is Emerald
Emerald is the most prized variety of the mineral Beryl. It sometimes fetches higher prices than diamond. It appears as pale green to bright green.
Though it is the green variety of beryl, not all gem-quality green beryls are called emeralds; yellow-green stones are called "heliodors;"soft blue-green or even pale green specimens are called "aquamarines".
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The birthstone for June is Pearl
Pearl is one of four main ornamental materials that are classified as "organic" gems, the other three being coral, ivory, and amber. About 92 percent of pearl is calcium carbonate, in the form of aragonite crystals, held together by an organic substance (concholin), which is identical to the horny outer layer of oyster shells, plus a small quantity of water. Mother-of-pearl has a similar chemical composition, but with less calcium carbonate, and more water, and is used as the nucleus of cultured pearls.
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The birthstone for July is Ruby
The color varies from fiery vermilion to violet red, but because rubies are pleochroic, different colors are also found in the same stone; bright or sometimes brick red in one direction, tending to carmine in the other.
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The birthstone for August is Peridot
Peridot is the greener type of gem-quality specimen of Forsterite-Olivine, which is an important, rock-forming mineral, a silicate of magnesium and iron. Often their names are used interchangeably. The bottle-green/olive green type of olivine is also called olivine. The yellower type of olivine is called Chrysolite.
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The birthstone for September is Sapphire
Sapphires can be a very dark blue, to the point of seeming dense and blackish from a distance, sometimes accompanied by a blue to dull green pleochroism, which is only visible from the side in cut stones. They may also be a strong, but not too bright blue, easily recognizable from a distance, this being the real color. Other possibilities are light, usually bright, blue.
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The birthstone for October is Opal
Opal is hydrated silicon dioxide. It has the same chemical composition as quartz but contains about one-tenth (and sometimes as much as one-third) water.
It is never crystalline, but it displays a rich play of colors, or "fire" caused by the internal refraction of light by the array of tiny spheres of amorphous silica which for a compact, three-dimensional network in the mineral.
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The birthstone for November is Citrine
Citrine is an attractive type of quartz, which is the commonest mineral on the earth's surface. But citrine itself is an uncommon macrocrystalline variety. Its yellow color brought about by its iron hydrate content, its reddish yellow from a trace of ferric iron. It forms hexagonal prisms, terminated by pyramidal shapes. Its faces are often striated, and the crystals twinned and distorted, having an uneven fracture at its base. It occurs in granular, stalactitic, and cryptocrystalline habits. It is a transparent to translucent mineral, and has a vitreous luster on fresh surfaces.
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The birthstone for December is Citrine
Turquoise is a hydrated phosphate of copper and aluminum in the Phosphates, Arsenates, Vanadates group, with a triclinic crystal system.
It rarely occurs as prismatic crystals. It is usually found as light-blue or green masses, nodules, and veins, sometimes filling cavities in various rocks. When it occurs as thin strips, it is tighter and brightly-colored at the center, lighter and porous on the outside.
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