What Is Tourmaline? A Mineral Family, Not One Stone

Tourmaline isn't a single mineral — it's a complex group of chemically related borosilicate minerals sharing the same crystal structure but differing in exact composition, which is why it occurs in more colors than almost any other gem material.

The Species Within the Group

Different tourmaline species are named for their dominant chemistry: schorl (iron-rich, black, the most common tourmaline by far) elbaite (lithium-rich, responsible for most fine gem colors — pink, green, blue, multicolor), dravite (magnesium-rich, typically brown), and liddicoatite (calcium-rich, often showing complex color zoning). Iron tends to produce greens and blues; manganese produces pinks and reds; a single crystal can shift chemistry as it grows, producing multicolor zoning within one stone — "watermelon tourmaline," with a pink core and green outer rim, is the best-known example of this.

An Unusual Electrical Property

Tourmaline is both piezoelectric (generating charge under pressure, like quartz) and pyroelectric (generating charge when heated or cooled) — a genuinely uncommon combination. Historically, this meant a warmed tourmaline crystal could attract small bits of ash or paper, which reportedly puzzled and fascinated 18th-century Dutch traders who nicknamed it "aschentrekker" (ash-puller) before its properties were scientifically understood.

Paraíba Tourmaline

Copper-bearing elbaite tourmaline, producing an intense, almost electric blue-green unlike any other gem material's color, was first discovered in Paraíba, Brazil, in the late 1980s. It remains extremely rare and among the most valuable colored gemstones by weight, with similar copper-bearing material later found in Nigeria and Mozambique, generally sold under the same trade name due to the shared color-causing chemistry.

Where It's Mined

Brazil is historically the most significant source across multiple tourmaline colors; Nigeria and Afghanistan are major current producers of a wide range of gem tourmaline.

Quick Facts

Mineral family: complex borosilicate group (schorl, elbaite, dravite, liddicoatite) — Hardness: 7–7.5 on the Mohs scale — Both piezoelectric and pyroelectric — Rarest variety: copper-bearing Paraíba tourmaline — Major sources: Brazil, Nigeria, Afghanistan.