eli5 What determines whether a gem is a sapphire, ruby, emerald, diamond, etc if those gems don’t necessarily have to be the most common thought color? For example, sapphires can be colors other than blue. What’s the difference between a red sapphire and a ruby? Submitted by Catnicorn99 t3_11c5r13 on February 26, 2023 at 4:54 AM in explainlikeimfive No comments 1