Large Rainbow-coloured Carborundum Crystal Display Specimen

Comprising three rounded geodes, to be cut or cracked open. 460 grams total, 50-65 mm



From Brazil. Ex Mineral Imports, London, UK. Gregory, Bottley & Lloyd (Gregory's), Harwich, UK.

Each with a polished face showing an internal cavity, some with a dusting of crystals inside. 985 grams total, 53-71 mm



From Brazil. Ex Mineral Imports, London, UK. Gregory, Bottley & Lloyd (Gregory's), Harwich, UK.

Comprising lacquered porphyry slice of irregular shape, cut and polished on one side, probably recycled material mined in ancient Roman times between the 1st and 5th century A.D. 443 grams, 18.2 cm



From Egypt. Ex Mineral Imports, London, UK. Gregory, Bottley & Lloyd (Gregory's), Harwich, UK.

Mons Porphyrites (today Jabal Abu Dukhkhan) is the mountainous site of a group of ancient Porphyry quarries in the Red Sea Hills of the inhospitable eastern desert in Egypt, a five day trip from the Nile during Roman times. They were discovered by Caius Cominus Leugas in 18 A.D., and during the Roman Empire the mines officially belonged to the emperor and were the only known source of the Imperial Porphyry, Mons Porphyrites. This dark purple stone was associated with royalty and used for prestigious sculpture and architecture. The location of the mines was lost some time in the 5th century, and rediscovered in the early 19th century. Excavations in the area have revealed the well-preserved quarries and the dwelling places of the quarry men, and also thousands of ostraca have been discovered containing messages that provide details of how the quarrying took place, and of how the highly skilled quarrymen ordered their food.