corundum, Sri Lanka.12, inclusions.5, synthetic corundum.7, gems

This paper describes the identification and crystallographic orientation of the rutile inclusions found in a corundum from the Elahera area, Sri Lanka. The corundum crystals are heavily zoned (fig. 1). The rutile inclusions are almost invariably twinned—either of a needle-like habit with two individuals or geniculated with three or four individuals. The twin plane is {1011} and the needle axis is ⟨011⟩. The orientation of the rutile inclusions in the corundum host is as follows: • Rutile ⟨010⟩ || Corundum [0001] • Rutile ⟨01T⟩ || Corundum ⟨11̅20⟩