Copyrights to fossils

I've been trying to find out if there are any laws pertaining to the right to copy fossils or copy other people's copies of fossils. Ethically, it seems to me that if you make a copy of a fossil from the original, then you should be able to disseminate or sell those copies as you wish. However, if you are the purchaser of that cast, then it seems to me that you should need permission to make a mold and further casts from it, particularly if you are doing this for profit or in such a way that would hurt the income of the owner of the original fossil.
However, as somebody who would very much like to make my own copies of a large number of fossils without paying royalties for them, I would hate to get sued for such practices. The problem that I see is that casts from legitimate institutions with original fossils are extremely expensive, much the same way that movie and music distributors gouge customers for their copy-written products. Thus, people are tempted to buy or sell essentially pirated fossils. The solution as I see it is a reduction in price from the owner of the original and clear copyright laws pertaining to fossils and other antiquities. I understand that it is very expensive to produce a cast of a fossil (the mold actually being the most expensive part usually), but if many are sold, then it reduces the unit cost in terms of the production of the mold. Another complicating factor is that many paleontologists would prefer to have exclusive intellectual rights to their fossils, but choose to sell display copies at high prices to prevent people from writing papers from purchased casts. Thus, clear policies regarding fossils as intellectual property is also important.
All these logistics will only bog down the scientific process, and is an unfortunate side effect of the popularization and comercialization of paleontology.