Product Description
This is a 320-carat lot of natural Green Cap Tourmaline crystals. This is sourced from the Skardu mining region of northern Pakistan. The lot contains multiple elongated rough crystals, each displaying the characteristic dark body with a vivid green termination cap — a natural color zoning feature formed during crystal growth.
The crystals are elongated in form with striated surfaces typical of tourmaline. The green coloration is concentrated at the cap (termination end), while the body of each crystal is darker. Individual pieces vary in length, width, and the intensity of the green cap. The lot was measured using a digital caliper, confirming the size range of the crystals.
Product Details
- Gemstone: Tourmaline (Green Cap variety)
- Total Weight: 320 Carats
- Individual Crystal Size: 1 to 6 Carats (mix of 1–2, 2–3, 3–4, and 4–6 carat pieces)
- Color: Vivid Green cap with dark body
- Treatment: No Treatment — 100% Natural
- Origin: Skardu Mine, Pakistan
About Green Cap Tourmaline
Green Cap Tourmaline refers to tourmaline crystals that display a distinct green-colored zone at the termination (top) of the crystal, while the rest of the crystal body is darker — typically black or very dark green. This color zoning occurs naturally during crystal formation when the chemical environment in the growing medium changes over time.
Tourmaline is known for pleochroism, meaning the apparent color can shift depending on the viewing angle. In rough form, this is particularly noticeable when rotating the crystal under light. The green cap portion is the area most commonly evaluated for potential faceting, while the darker body sections are often used for specimen display or cabochon cutting.
Suitable For
- Mineral and crystal collectors
- Lapidary professionals evaluating green cap sections for faceting
- Gemstone dealers sourcing Pakistani tourmaline material
- Specimen display and natural crystal collections
- Beginners looking for a starter lot of natural tourmaline rough
Frequently Asked Questions
What is the difference between green tourmaline and green cap tourmaline?
Green tourmaline refers to crystals that are uniformly green throughout. Green cap tourmaline specifically describes crystals where only the termination end is green, while the rest of the crystal body is darker — this color zoning is a natural growth feature, not a treatment.
How many crystals are typically included in a 320-carat tourmaline lot?
The number of pieces depends on individual crystal size. With an average of approximately 3.7 carats per piece, a 320-carat lot typically contains around 85–90 individual crystals, though this varies based on the actual size distribution within the lot.
Is Pakistani tourmaline considered good quality for lapidary use?
Pakistan, particularly the Skardu and Gilgit regions, is a recognized source of tourmaline rough used by lapidary professionals. The quality varies by piece, and SI-clarity material like this lot requires individual evaluation of each crystal for transparency, fracture placement, and color before cutting.