This gives the agate its colouring and hardness (7 - 7.5 on the Mohs scale, diamonds being 10).
(This; gives; the agate) (its colouring and hardness (7 - 7.5 on the Mohs scale, diamonds; being; 10)
This its colouring and hardness (7 - 7.5 on the Mohs scale, diamonds
gives being
the agate
10