Rubies and Sapphires belong to the same gemstone family, corundum, which is the mineral name for crystalline aluminum oxide. As they both have the same basic chemical composition, their physical characteristics are very similar; however, the presence of small amounts of various trace elements creates noticeable differences in colour.

raw-ruby

 

Ruby is red corundum while sapphire can be all the other colours in which corundum can occur – blue, pink, green, yellow, orange, purple and others. As they share the same physical characteristics, a similar approach is taken to both when cutting, although differences in the shape of rough material from various locations may mean the lapidary must take into account various other considerations......

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