Well, for several reasons. The reason we cannot value a specimen is we do not have the ability to physically test it. The lead for example, we don't know the purity of it. So we could tell you that lead is worth 38 cents per pound. That is not what it is worth but an example. We could do the math and say his sample was worth whatever the current price is. That could change by the day. But it will also change by the percentage of lead in the sample. It just isn't possible. It is also impossible to value a gem without being able to see inclusions and some other tests. We recommend taking samples to a mineral or rock shop near you, or even a jeweler. There is a lapidary who cuts gems, too and rocks. The lapidary can evaluate how much of a stone is useable. He can look at the crystal lattice and see inclusions and imperfections, we simply cannot see those in a picture. Then, he can value the stone by how much the finished cut stone is worth and not just the weight of a specimen. I hope that helps to show our limitations. It isn't that we don't want to, it is that we cannot do so accurately.