I don't know but they are gorgeous
Keep in mind putting wood in your aquarium may or may not turn the water yellow. It is caused by chemical know as tanins. They are not harmful. They actually bind heavy metals in the water which are harmful. You can use activated carbon to remove the yellowing if you wish. Also...You could try pre soaking them. There is much paranoia in the hobby and many will tell you OMG don't do that. Unless someone sprayed herbicides and pesticides all over this wood it will most likely be just fine. May float a bit until it gets water logged.