While holding a Soulstone, right click on a tamed pet or mount to bind it to your spirit allowing you to summon and dismiss it anywhere anytime. The Soulstone is consumed when used and can stack. Bound pets or mounts will respawn after death and have natural health regeneration. Your spirit can only summon so many bound pets or mounts at one time and recharges at a slow pace.
Soulgazer, Enderpearls, Diamonds.