Topacio Imperial
Topacio is a mineral with formula Al₂SiO₄(F,OH)₂, in the Silicatos (Nesosilicatos) group. This specimen comes from Ouro Preto, Ouro Preto, Minas Gerais, Brasil and joined the Terrium collection in 2025.
Description
Short, robust prismatic crystal with striated faces and a clean upper pinacoid. Golden-orange colour with honey tones, internal cloudy zones, and good transparency at the apex. Under UV it shows an internal response, as if emanating from the core. The specimen fits the "rough gem" type, compact and well proportioned, with classic features of the Ouro Preto imperial variety.
About Topacio
Topaz is an aluminium and fluorine nesosilicate with Mohs hardness 8 and perfect cleavage. The imperial variety is distinguished by warm colours—golden, honey, orange—and by its transparency. Brazilian specimens are considered the world standard for quality and typicality.
About the locality
Ouro Preto is the type locality of imperial topaz and the most famous in the world for this variety. Its late-magmatic pegmatites produce prismatic crystals of warm hues, highly regarded in gemmology and collecting.
Technical data
- Catalogue No.
- 0196
- Composition
- Al₂SiO₄(F,OH)₂
- Name
- Topacio
- Variety
- Imperial
- Group
- Silicatos (Nesosilicatos)
- Category
- Estélites
- Mine
- Ouro Preto
- District / Municipality
- Ouro Preto
- Province
- Minas Gerais
- Country
- Brasil
- Size (cm)
- 1.5 x 1.2 x 0.8
- Acquired
- 2025
- Etymology
- From the Greek "topazos", the name of an island in the Red Sea (now Zabargad), although the mineral so named was not topaz.
- Quality
- Muy buena
- Value trend
- Al alza
Related specimens
- Ágatha — Brasil
- Cianita — Brasil
- Cianita (Negra) — Brasil
- Cianita (Negra (Taramita)) — Brasil
- Clinocloro — Italia
- Amatista — Brasil
- Cuarzo — Brasil
- Elbaíta (Verdelita) — Brasil