Precious stones, they come in two forms, uncut and cut. Value alone doesn't tell us much as this could represent just one or two fabulous stones or an entire handful of lesser quality stones. On top of this, the fact that these stones could be either cut stones or uncut stones, in either of these cases it would require someone with a great deal of knowledge about precious stones in order to have placed accurate value on them. And as for uncut stones, well, the value of these stones could multiple many times once they were cut. So the bottom line here is that in order to have placed an accurate value on the alleged stones then the exchange would have required at least one very knowledgeable and an extremely trusted participant, or, the value of these alleged stones were determined before the actual exchange. If the later is true then the evidence would suggest that the actual exchange was prearranged.