Sapphire Blade?

Question

Is it possible to make a sapphire blade for a sword. Wouldn't this also be quite cheap if you were to use lab created sapphire? Do you know where you can get one made?

Answer 1

Sapphire and other hard minerals are too brittle to be made into swords.

The diamond or sapphire blades you may have heard about are steel with a coating of microscopic diamond/corundum. This doesn't make them much sharper but they make thin blades last longer

Answer 2

You would be able to make a small blade, such as for a scalpel. But to make a large blade, to be used in combat, it would not work. The sapphire would be too brittle and break easily.This is the same reason why you don't see full fledged swords made out of flint used in battle. Though it might look nice hanging on a wall in use it would be useless.

The hardness of sapphire is 9.0 (diamond is a 10.0) so the blade would be hard but very brittle. This is why you do not wand a lot of carbon in a steel blade. Carbon will make the steel blade hard and make it hold an edge but it will also make the blade brittle and prone to breaking.

Answer 3

I know that a diamond blade as used in lab instruments is insidiously sharp.  It can create such fine incisions that you don't know you are cut until severely injured.  Sapphire has a different crystal structure from diamond.  So....?? hmmm