[Solumina]

One of the reasons why it is so expensive at the moment is that both India and China have banned the export of human remains and those used to be the two main suppliers. Bones used to be a lot cheaper and some places still have stockpiles from before the ban (China's ban went into effect in 2008) and have low-ish prices.

Personally I don't get why anyone would want human bones for jewelry (other than the "oooo I'm so spooky" factor) as animal bones are much cheaper and come in a wide variety of shapes and sizes, meaning that you can get a much more interesting, intricate piece for a lot less money.