Ruby Ores

Ruby ores should be extremely rare and they should be max 2 for every vein. the Ruby tools and armor would be more weak compared to the diamond tools and armor, and they should be used as a secondary currency for the villagers to trade more expensive items, for example high-level enchanted books. And of course, like all other ores, rubies should have a ruby block. 

It should generate in deepslate and in normal stone, but it should be even more rarer in normal stone.