Cyanite

Level by level

1. Poor5 %
2. Common10 %
3. Uncommon15 %
4. Rare20 %
5. Epic30 %
6. Legendary50 %
7. Ascendant75 %
8. Godlike115 %

The enchantment that does the same

Monster Slayer increases the same thing, and reaches +65 % where this reaches +115 %.

1. Poor2.5 %
2. Common5 %
3. Uncommon7.5 %
4. Rare10 %
5. Epic15 %
6. Legendary25 %
7. Ascendant35 %
8. Godlike65 %

A piece carries one of each, so the two add rather than compete. Where you can only feed one, feed the gem.