opal var. Hyalit – Valec, Doupov, Karlovy Vary, Czech Republic
 Found 1999
 
 Sculptural Hyalite on matrix. This mineral usually occurs as a crust, the spherical crystals rarely build up to 1.8 cm. This variation of opal is mostly highly fluorescent, but this is not the case for this piece. Although specimens from the same find fluoresce, this hyalite shows no reaction under UV light. Unharmed, rare collector's item from the Czech Republic with a good lustre.