GIA Gem Encyclopedia | Complete List Of Gemstones
GIA’s Gem Encyclopedia is a virtual journey through the science and lore of gemstones from across the globe. Each precious stone page features additional detailed gemological information, a buyer’s guide, photos, videos & research. Filter By Country. View Gems as. Polished.
What is Topaz Gemstone | Topaz Stone – GIA
Topaz is a precious stone, typically colorless, yellow & is Allochromatic, which means that its color is caused by defects in its crystal structure.
Sapphire Gemstone | Sapphire Stone - GIA
Color. Sapphires come in a variety of colors. Preferred sapphires have strong to vivid color saturation, regardless of hue.
Amethyst Gemstone | Amethyst Stone - GIA
Amethyst Gemstone is the purple variety of the Quartz mineral. Amethyst’s purple color can range from a light lilac to a deep, intense royal purple, and from brownish to vivid.
Birthstones | Birthstone by Month - GIA
Sapphire, the September birthstone comes in all the colors of the rainbow – except red. Learn more about the birthstone of wisdom, loyalty and nobility and discover its history and where it can be found. Opal and tourmaline are the two birthstones for October.
What Is Tourmaline Gemstone | Tourmaline Stone – GIA
Tourmaline’s colors have many different causes. It’s generally agreed that traces of iron, and possibly titanium, induce green and blue colors. Manganese produces reds and pinks, and possibly yellows.
Aquamarine Gemstone | Aquamarine Stone - GIA
Aquamarine’s most valuable color is a dark blue to slightly greenish blue. Like all fine aquamarines, this gem is free of eye-visible inclusions. This fine 3x3x7 cm aquamarine mineral specimen is from Balistan, Pakistan. The crystal shows aquamarine’s typical six …
Spinel Gemstone | Spinel Stone - GIA
Color. The most valued spinel colors are bright red, cobalt blue, and vivid pink and orange. Pale lavender is more affordable
What Is Jade Gemstone | Jade Stone – GIA
Color. The finest jadeite—almost transparent with a vibrant emerald-green color—is known as “imperial jade.”
What Is Tanzanite Gemstone | Tanzanite Stone – GIA
Tanzanite is an extraordinary gemstone, its appearance is influenced greatly by its ability to show colors when viewed from different directions.