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
Elongate, thin, very transparent prismatic crystal with well-defined fine vertical striations and a light honey colour with a slight orange tint. It terminates in a flat end with a small growth step and shows clean internal zones with scattered inclusions. Shows a weak but appreciable response to ultraviolet light on the lateral faces and upper portion.
About Topacio
Topaz is an aluminium–fluorine nesosilicate with hardness 8 and perfect cleavage. The imperial variety is characterised by its warm colour range, high transparency and prismatic habit. Brazilian pieces set the world standard for quality and typicality.
About the locality
Ouro Preto is the type locality of imperial topaz and the most famous worldwide for this variety. Late-magmatic pegmatites produce prismatic crystals with warm hues, highly regarded in gemmology and collecting.
Technical data
- Catalogue No.
- 0198
- 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)
- 2 x 0.7 x 0.5
- 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