If you're talking about dry base rock, there's no need to do anything other than rising the shipping residue from it. I've "cured" dry base rock in the past... but the last few times I've purchased any, I've given it a good blasting with a water hose, dried it in the sun for a day, and placed it directly in the tank. Most dry base rock, often called "reef saver" rock, comes from ancient reefs that were landlocked eons ago. There is nothing living (or dead) in this rock to cause an ammonia spike, so it's safe to use right away. It will become live faster in a tank with live rock than it will by "cooking" it in saltwater alone. Just my 2c...