Verdelite

Verdelite is the traditional trade name for green gem tourmaline, almost always a green-colored variety of the lithium tourmaline elbaite. The name combines the Latin and Italian roots for green with the suffix used across tourmaline varieties.

Greens span a wide range, from light yellowish and grass tones to rich blue-green and dark forest hues. The most prized bright, saturated greens colored by chromium or vanadium are sometimes marketed separately as chrome tourmaline.

Verdelite is one of the most available and affordable tourmaline colors and a perennial favorite for jewelry.

Like other elbaite varieties, verdelite crystallizes in granitic pegmatites from boron-, lithium- and water-rich residual melts and fluids during the final stages of granite solidification. The green color comes mainly from iron, sometimes with chromium or vanadium.

Crystals grow as long prismatic forms in pockets alongside quartz, feldspar, lepidolite and other gem tourmalines, and a single crystal can grade between green and other colors.

Major sources include Brazil (Minas Gerais), Afghanistan, Pakistan, Nigeria, Mozambique, Madagascar and the United States (notably Maine and California).

Verdelite shows the typical tourmaline habit: elongate prismatic crystals with rounded triangular cross-sections and strong lengthwise striations. Hardness is 7-7.5, with vitreous luster, white streak and no cleavage.

A key diagnostic is strong pleochroism: green tourmaline usually looks darker down the length of the crystal than across it, which cutters orient carefully. This dichroism helps separate it from emerald, green garnets (tsavorite, demantoid) and peridot.

Unlike emerald it is far less included and lacks emerald's distinctive inclusions; unlike garnet it is doubly refractive and strongly pleochroic.

Verdelite is widely used in rings, pendants and earrings, valued for its durability and broad range of attractive greens at accessible prices. Vivid chromium-rich stones fetch a premium.

It is one of the cornerstone gem tourmalines in the trade and pairs popularly with pink tourmaline in bicolor and suite jewelry. Larger clean stones are cut into showcase gems for collectors.

In metaphysical practice green tourmaline is associated with the heart and vitality, though such claims are not scientifically verified.