Occurrences of opal in the Central American country Honduras are already known since the mid-19th century. Opals with and without playof-colour are found in volcanic rocks, especially in mostly strongly weathered andesites and in ignimbrites. Generally, white and light opals, partly with dendrites, brown to yellowish and dark matrix opals can be differentiated. The occurrences are located in the Departamento Lempira in the Region of Erandique. A new occurrence exists in the Departamento Ocotepeque, west of Lempira.

This article deals with the macro- to microscopical characterization of the different opal types from Honduras, their physical and chemical properties and micro-structures.

This article was published in German with an English abstract and English figure captions in our Journal. DGemG-members have access to the article in our online-archive.

Authors

Dr. Ulrich Henn, DGemG,
Stefan Müller, M.Sc., DSEF,
Qi Wang, M.FA., FGG, EG and
Anaité Seibt, ALS Opalos, La Ceiba, Honduras