Raw Black Tourmaline Value Guide

Raw Black Tourmaline, scientifically known as schorl, is a highly sought-after mineral specimen prized for its deep opaque luster and unique pyroelectric properties. These Brazilian specimens are particularly collectible due to their distinct trigonal crystal habit and historical significance as the 'aschentrekker' or ash-puller of the 18th-century Dutch trade.

What affects the value of Raw Black Tourmaline?

• The presence of well-defined, undamaged crystal terminations significantly increases the market value.
• Specimen size and weight, with larger unpolished pieces typically commanding the $25.00 price point.
• The luster of the crystal faces, where a glassier or more vitreous sheen is preferred over duller surfaces.
• Structural integrity, specifically the absence of excessive crumbling or major fractures within the schorl matrix.

How to Identify Raw Black Tourmaline?

• Examine the specimen for a distinct trigonal (three-sided) crystal system with vertical striations along the prism faces.
• Verify the deep, opaque black color which should show no transparency even when held up to a strong light source.
• Check for a brittle tenacity and a conchoidal to uneven fracture pattern typical of natural unpolished schorl.
• Confirm the origin as Brazil, which is a primary source for high-quality, well-formed schorl columns.

History of Raw Black Tourmaline

Tourmaline has been known since ancient times in the Mediterranean, but it was not until the early 1700s that Dutch traders began importing it from Sri Lanka to Europe. They noticed that the stones, when heated, would attract and repel hot ashes, leading them to call it 'aschentrekker' or ash-puller. Black tourmaline, or schorl, was historically used in mourning jewelry and is now widely popular in mineral collecting for its distinct trigonal crystal habit.