Ruby Ore

Ruby Ores are semi-rare ores that can be smelted to obtain Rubies. They can be found at the middle of the coal layer and the gold layer. They can be harvested only via Iron Pickaxe or stronger. The ore can be harvested with Silk Touch enchantment.

in MUI 1.17.0
This allows you to make ruby armor and swords

ruby armor defends 10

and if a mob attacks you get jump boost for 1 second (jump boost 4)