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
Pale champagne colour. Tall, slender prismatic crystal with fine vertical striations and high transparency. It terminates in an inclined pinacoid with slight irregularities and shows scattered small internal inclusions. Shows a weak response under UV. Notable for its lightness of colour and optical purity, representing the palest and most delicate tone of the group.
About Topacio
Topaz is an aluminium-fluorine nesosilicate with hardness 8 and perfect cleavage. The imperial variety is characterised by a warm colour range, high transparency and prismatic habit. Brazilian pieces are 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. Late-magmatic pegmatites produce prismatic crystals with warm tones, highly prized in gemmology and collecting.
Technical data
- Catalogue No.
- 0193
- 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)
- 2.2 x 1 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