STONE

Topaz

Transparent topaz used as a gem; natural and treated material occurs in several colours.

Typical colour: Colourless, blue, yellow, orange, pink and others
Also known as: Топаз
Birthstone: November A modern tradition, not a property of the stone. GIA

Editorial mineral illustration for Topaz — AI-generated editorial illustration; not a specimen photograph, museum object, or locality evidence.

FOUND IN TAJIKISTAN

Topaz, including blue crystals, occurs in the granite pegmatites of the Rangkul' field near the Turakuloma (Kukurt) ruby district, Eastern Pamir.

Mindat — Rangkul' pegmatite field, Rangkul' Highlands, Gorno-Badakhshan

WHAT IT IS MADE OF

Mineral science

Physical and optical properties belong to the mineral species; see the mineral page for the full sourced profile.

What causes the colour

Besides brown, topaz occurs in blue, green, yellow, orange, red, pink and purple. It is pleochroic: one crystal can show different colours in different directions.

Treatments

Colourless topaz is plentiful and is often treated to turn it blue; irradiating it with high-energy (10 MeV) electrons creates a sky-blue colour.

History and names

The royal court of Portugal celebrated the discovery of Imperial topaz in 1768. A transparent topaz crystal weighing 596 pounds was found in Minas Gerais, Brazil.

COLLECTION

Study views

SOURCE

GIA Gem Encyclopedia — Topaz