Vinh...I have a BUNCH of petrified wood ROCK....a lot that I've never used and some that I have used in my freshwater cichlid tanks that I don't have anymore. I was gonna call one of the LFS's and see if they wanted to buy it from me....How much are you looking for? I have big...med...& small rocks...makes for a great freshwater tank. Let me know if I can help....