Minerals and Metals in Ancient India v2.c41.s4.13

v2.c41.s4.13

Ruby is the clear red variety of kuruvinda (2.14.48) or corundum (Al₂O₃) containing chromium and a little iron; this is known in India as padmarāga, māṇikya or cuṇi. Balas-ruby is rose-red and was known as bālasūryaka (like the morning sun). This spinel probably came from Badakshan. Rubicelle, which is yellow, was known as karuṇḍaka. Deep red spinel or spinel ruby MgAl₂O₄, identified with saugandhika, actually belongs to a different (spinel) family of minerals. Many other classess of gems could have red colour.