3 Burmese Blue Sapphire Crystals. Good colour and crystal form. We collected these three from Myanmar several years ago when they were a lot easier to get.
Ruby Corundum: Al2O3.
Corundum is called Sapphire except red Sapphire which is called Ruby. A rare sapphire is a Padparadscha which is a pinky peach colour, found in Sri Lanka. The best shade of red for a Ruby is Pigeon Blood Red. Ruby can be any shade of red up to almost pink.