OCR Text |
Show Brazilian Pebbles. Brazilian pohblo Is a namo given to largo masses of particularly transparent transpar-ent quartz or rock crystal, which Is most abundantly found In Brazil, although al-though mnterlal qulto as good occurs somewhat sparingly In Switzerland nnd Madagascar As regards transparency trans-parency nnd hardness tho Brazilian pebblo was far superior to. tho host product of tho old, glass melters, but tho modern glass Is quite ns good as tho crystal In fact tho mineral Is now Httlo used, and tho name porslstB mainly ns a trade optthct Intended to express superior quality Good Ri..a for lenticular purposes is now made in tho United States, but tlo be3t, such ns would ho employed in astronomical astro-nomical and microscopic work, still comes from France and Germany. |