Gemstone Education

Gemstone Education

Gemstones A-Z

A free informational reference guide to gemstones

  • Alexandrite
      June Birthstone : The Alexandrite was discovered in 1830 in Russia's Ural Mountains. Often descirbed as "emerald by day, ruby by night," alexandrite is a very rare color changing stone of green, brown or purplish red. Alexandrite is also the gem for the 55th wedding band. (GIA)
  • Amber
    Amber: While amber isnt a birth stone, it is associated with the astrological sign of Tauras. Amber is a organic gem. Organic gems are products of living or once living organisms and biological processes. Amber formed 10 million of millions of years ago, when sap from ancient trees hardened and fossiled.The oldest amber dates back 320 million years ago (GIA)
  • Amethyst
    Februrary Birthstone: Amethyst was as expensvie as ruby and emerald until the 19th century, when Brazil's largest deposit where discovered. It was believed to prevnt intoxiation-amethystos  means "not drunk" in ancient Greek. Amethysty is not only the Februrary birthstone but the gem for the 6th and 17th wedding anniversary (GIA)
  • Ametrine  
    Wether projecting from pegmatite walls or encrusted cavities in volcanic rock, quartz abounds world wide. People have used quartz in jewelry for thousands of years. When quartz displays colors of amethyst and citrine in the single gemstone it is called ametrine or amyethist-citrine. Ametrine is only sourced in Anahi Mine in Boliva (GIA)
  • Aquamarine
    March Birthstone: Aquamirine's name comes from the latin for seawater and is said to calm waves and keep salors safe at sea. Marches birthstone is also thought to keep happiness of marriages. Aquamarine is mined at high elevations in Pakistan's Karakoram Mountains. This gem is also used for 19th wedding anniversary (GIA)
  • Citrine
    Along with topaz, citrine is the Novemeber birthstone and is recognized for being the gemstone for the 13th anniversary gift. Citrine is rare in nature. Citrine is recognized as one of the most popular and frequently purchased gemstones (GIA)
  • Diamond
    Diamonds are amoung nature's most precious and beautiful creations. Diamonds form under high temperature and pressure and pressure conditions that exist only 100 miles beneath the earths surface. Diamond's carbon atoms are bonded in essentially the same way in all directions. Diamonds are the hardest mineral on earth: 58 times harder then anything else in nature. A diamond is recongnized today as April's birthstone. Diamond is also the gem the marks the 60th and 75th wedding anniversary (GIA)
  • Fancy Color Diamond
    Dazzing Brillance. Captivating Color. The plant's most valued gems are fancy colored diamonds. Gem diamonds in GIA's range usually range from D-to-Z range usually decreases in value as color becomes more obvious. Just the opposite happens with fancy color diamonds. Their value generally increases with the strength and purtity of the color. Large, vivid fancy color diamonds are extremely rare and very valuable. Diamonds are the birth stone for April and the 10th and 60th anniversary (GIA)
  • Emerald
    Emerald is a blueish green to green variety of beryl, a mineral species that includes aquamarine. Gem experts differ on the degree of green that makes on stone and emerald and another a less expensive green beryl. Emeralds are mined in Africe, South America and Asia. As a gem of spring emerald is a perfect birthstone for May. It is also the gem for the twentieth & thiry-fifth anniversary. 
  • Garnet
    Garnet are a set of closely related minerals forming a group, with gemstones in almost every color. Red Garnet have a long history, but modern gem buyers can pick from an assorment of almost every color. Red garnet is one of the most widespread of the gems. But not all garnet is as abudant as red ones. A green garnet, tsavorite, is rarer and needs rarer rock chemistries and conditions to form. Garnet is the birthstone for January and 2nd anniversary (GIA)
  • Iolite
    According to ledgend , Vikings used to use Iolite to reduce glare when checking the sun's position. Iolite's name comes from Greek word ios, meaning violate. Iolite is not typplically treated. Iolite is the gemstone for the twenty-first wedding anniversary. 
  • Jade
    Jade is actually two seperate gems: nephrite and jadeite. In China, a pierced jade disk is a symbol of heaven. Jade is the offical gem for the 12th anniversary.
  • Kunzite
    Kunzite is the best-known variety of the mineral spodumene. Its named after famed gemologist George Fredrick Kunz, who was the first to identify it as a unique varieyt of spodumene. Kunzite gets it delicate color from trace of manganese. California San Diego County is an important source of Kunzite (GIA)
  • Lapis Lazuli
    Lapis was treasured by the ancient civilizations of Mesopotamia, Egypt, China, Greece, and Rome. This ancient rock is an aggregate of several minerals. The three major minerals that comprise lapis are lazurite, calcite, and pyrite. 
  • Moonstone
    Moonstone unearthy glow is caused by light scattering between microscopic layers of feldspar. The minerals in feldspar make up 1/2 of the earths crust. Moonstone is te birthstone for June, along with alexandrite and pearl (GIA)
  • Morganite
    Morgaite subtle color is caused by traces of maganese. A strong color in morganite is rare, and gems usually have to be large to achieve the finest quality (GIA)
  • Opal
    Because opal has the colors of other gems, the Romans thought is was the most precious and powerfull of all. The Bedouins believed opal contained lighting and fell from the sky during thunderstomers. Opal contains up to 20% water trapped in its silica structure. Opal is the birthdstone for October (GIA)
  • Pearl
    Perhaps the best-loved gems of all-time, pearl-natural and cultured- occur in a varitey of colors. The most familiar are white and cream, but the palette of colors extends to every hue. Natural pearls form around a microscopic irriant in the body of certain mollusk.Cultured pearls are the result of the deliberate insertion of a bead or piece of tissue that the mollusk coat with nacre (GIA)
  • Peridot
    Found in lava, meteorites, and deep in the earths mantle, yellow-green peridot is the extreme gem. The ancient Egyptians mined peridot on The Red Sea island of Zabarag, the source for many large fine peridots in the worlds museums. The Egyptians called it the "gem of the sun". Peridot is the birthstone for August and 15th anniversary gemstone (GIA)
  • Rose Quartz
    The color of rose quartz ranges from very light pink (almost white) to medium dark pink. The most appealing color typically occurs in largers sizes; small rose quartz specimens with good color are scarce. Rose quartz has been recognized as the gem that commeorates the fifth wedding anniversary (GIA)
  • Ruby
    Ruby can command the highest per carat price of any other color stone. This makes ruby one of the most important gems in the colored stone market. In its purest form, the mineral corundum is colorless. Ruby is the birthstone for july and the gem for the 15th and 40th anniversaries (GIA)
  • Sapphire
  • Spinel
  • Sunstone
  • Tanzanite
  • Topaz
  • Tourmaline
  • Turquoise
  • Zircon


Green in sunlight. Red in lamplight. Color-changing alexandrite is nature’s magic trick.


Often described by gem aficionados as “emerald by day, ruby by night,” alexandrite is the very rare color-change variety of the mineral chrysoberyl. Originally discovered in Russia’s Ural Mountains in the 1830s, it’s now found in Sri Lanka, East Africa, and Brazil, but fine material is exceptionally rare and valuable.


Alexandrite is a birthstone for June, along with pearl and moonstone. Alexandrite is also the gem for the 55th wedding anniversary.


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