Large tumbled black tourmaline (schorl variety) from Brazil. Size between 40 and 58 mm, weight between 44 and 74 grams: volumetric format suitable for use as a hand stone, large pocket stone, or central piece in macrame compositions. The surface is polished to a river stone-like finish that neutralizes the typical fragility of rough crystal.
Material Data Sheet
| Mineral |
Black Tourmaline (Schorl) — boron silicate from the tourmaline group |
| Color |
Intense opaque black with vitreous luster on polished surfaces |
| Size |
40-58 mm diameter; 44-74 g weight per piece |
| Shape |
Tumbled (tumbling); "river stone" finish with no sharp edges |
| Finish |
Smooth polished, characteristic of tumbled stones |
| Hardness |
7-7.5 Mohs — high hardness, scratch-resistant in daily use; the tumbled format also neutralizes the rough crystal's tendency to cleave along planes |
| Origin |
Brazil — tourmaline deposits in Minas Gerais state, the world's most important in commercial production |
| Treatment |
Untreated. The black color comes from the native chemical composition of the mineral (schorl, with iron and manganese) |
| Type of piece |
Unique shape for each tumbled stone; shipped by intuitive selection within the size and weight range |
Why the tumbled format for black tourmaline
Rough tourmaline crystal presents as elongated prisms with longitudinal striations and distinct cleavage planes. Although its hardness is high (7-7.5 Mohs), the crystalline structure makes the points prone to breaking or chipping with regular handling. The tumbled finish eliminates these fragile points by rounding the perimeter, leaving a continuous surface resistant to daily use. It is the most practical version of the mineral to carry by hand, in a pocket, or as the centerpiece of a large pendant.
What this format is good for
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Macrame for large pendants — the 44-74 g weight is ideal for statement pendants with thick waxed thread; the ergonomic shape can be tied directly without a cap or adhesives
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Wire wrap — high hardness allows for thick gauges (1-1.5 mm) without risk of marking the polished surface; large formats work as a central piece in impactful pendants
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Large pocket stone / hand stone — the 40-58 mm size fits in a closed palm like a worry stone; black tourmaline is traditionally associated with personal protection and grounding
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Decorative compositions and altars — the visual mass and intense black create a strong focal point on light surfaces; traditionally used in "energy cleansing" compositions for spaces
Black tourmaline in cultural tradition
Black tourmaline (schorl) has been known since European antiquity for its piezoelectric and pyroelectric properties: when rubbed or heated, it generates a weak electrical charge that attracts light particles. Dutch sailors in the 18th century used it to clean ash from meerschaum pipes, taking advantage of this property, which earned it the alternative name "aschentrekker" (ash-puller). In modern crystal therapy readings, it is associated with personal protection, grounding, and filtering "dense energies," a reading that extends its documented physical behavior of electrostatic attraction.
The symbolic properties attributed to minerals belong to cultural and historical traditions. They are shared for educational purposes, not as medical advice or a substitute for professional care.
How to recognize genuine black tourmaline
Authentic black tourmaline is opaque with a vitreous luster on polished surfaces, not metallic or resinous. Its density is remarkably high (3.0-3.2 g/cm³): a 50 mm tumbled stone should weigh more than a similar-sized stone of obsidian or black glass. Under intense direct light, it may show subtle flashes of dark brown or very dark blue on thin edges. Black glass imitations are lighter in weight, show internal bubbles visible under a 10× magnifying glass, and their luster is uniformly vitreous without nuances. Black obsidian can also be confused, but its characteristic conchoidal (shell-like) fracture leaves very sharp edges that tourmaline does not have.
Frequently Asked Questions
Why the tumbled format and not rough crystal?
Rough tourmaline crystals have points and edges prone to breaking along cleavage planes. The tumbled finish neutralizes this fragility and leaves a continuous surface resistant to daily use, ideal for carrying in a pocket or as a hand stone. If you are looking for rough prismatic crystal, see the rough minerals collection.
How much does each tumbled stone weigh?
Between 44 and 74 grams. Those at the lower end (40 mm) are around 44-55 g; the large ones (58 mm) reach 70-74 g. The weight is notable compared to tumbled stones of other minerals due to tourmaline's high density (3.0-3.2 g/cm³).
Does it work for pendants?
Yes, for large pendants with macrame or thick-gauge wire wrap. The 44-74 g weight requires strong cord and a design that supports the load; it is not a lightweight everyday pendant but a statement piece with visual presence. For lightweight pendants, use the small-medium format from other selections.
Is it really piezoelectric?
Yes, all tourmalines (including black schorl) are piezoelectric and pyroelectric: they generate a weak electrical charge when mechanical pressure or temperature changes are applied. The property is very low in intensity and only measurable with instruments; the historical effect of attracting ash is due to this residual charge and the electrostatic attraction of light particles.
How do I care for it?
Clean with a soft cloth slightly dampened with water. The 7-7.5 Mohs hardness makes the material resistant to scratches in normal use. Avoid sudden impacts against hard surfaces, especially on the edges. More in the jewelry care guide.
Are there other pieces identical to this one?
No. Each tumbled stone has a distinct shape within the size range; the selection within each order is made intuitively from the available batch. If you need a specific size (minimum or maximum of the range) for a particular project, please indicate it in the order notes.
More about black tourmaline: properties, meaning, and uses. See also: all tumbled stones · meditation stones.
