Gemstone Encyclopedia

Imperial Topaz: Two Colors, One Crystal, and the Truth About Pink

Imperial topaz carries two colors at once: a permanent chromium pink and a fragile golden-orange made of lattice defects. Heat destroys one and leaves the other, which explains both the treatment t...

Kunzite: Why It Fades, Why It's Irradiated, What It Costs

Nobody digs for kunzite. It is spodumene, one of the world's main lithium ores, and it turns up while somebody is mining something else. That accident explains everything: why big clean stones are ...

Morganite: The Gem of Love, Grace, and Elegance

Morganite is the pink variety of beryl, named in 1910 after the banker J.P. Morgan and now one of the most requested engagement ring stones. Learn why its color builds with carat size, what routine...

Opal: The Mystical Gem of Light, Colors, and Magic

Opal is one of the most mystical gemstones, known for its unique color play and rarity. In this article, we explore its history, varieties, and the world’s most famous opals.

Peridot: The Gem of Sunlight, Prosperity, and Protection

Peridot is the only major gem born below the Earth's crust, and sometimes beyond it. Its story spans pharaohs, volcano goddesses and meteorites, told here with honest buying advice.

Quartz: The Gem Family Behind a Dozen Famous Stones

Most people already own quartz without knowing it; one vibrates in every quartz watch. How a single mineral becomes amethyst, citrine, agate and a dozen other gems.

Ruby: The Fiery King of Gemstones, Its History, Legends, and Investment Power

Ruby is the only major gemstone whose color and whose glow come from the same atom doing two different jobs. The rock it grew in decides whether the glow survives, and that single fact explains the...

Blue Sapphire Guide: Origins, Treatments, Value & Records

When the Blue Belle of Asia sold for 17.3 million dollars, the price was justified line by line on a single laboratory report. This guide reads blue sapphire the way the market does: five certifica...

Sphalerite: The Fiery Gem of Brilliance and Light

Sphalerite carries more than three times the fire of a diamond, with dispersion of 0.156 that no collectible gem approaches. Learn why transparent crystals are freak occurrences in zinc ore, why cu...

Sphene: The Fiery Gemstone with Unmatched Brilliance

Sphene, officially titanite, combines fire beyond diamond with the strongest facet-doubling effect in gemology, an interior that seems to move. Learn how its optical trio works, why chrome green st...

Spinel: The Hidden Treasure Among Gemstones

The most famous ruby in the British Crown Jewels is a spinel, and so are most of history's greatest red stones. Learn why spinel impersonated ruby so perfectly, why it reaches the market untreated ...

Tanzanite: The Mysterious African Gemstone, Its History, Legends, and Investment Value

Tanzanite begins with a Maasai legend of fire, a tailor who thought he found sapphire, and a Tiffany campaign that renamed a mineral. One hill below Kilimanjaro supplies the entire world, the depos...