Razz, as Barsenault pointed out, you may want to take a look at Chinese medal prices. Many are selling for considerably more than spot price on any given day (while most blobs are not) and plenty of Chinese medals are selling in the aftermarket for higher prices than their original issue price.
At any given time, millions of blobs are being sold by national (large) dealers at very close to spot or with some blobs, with no premium at all being added.
So your notion that medals' values are no different than that for common blobs is, to say the very least, faulty.
Additionally, a very low mintage high relief medal with special finish and COA & presentation box or capsule is a very different product than a common blob like this for example:
http://www.apmex.com/category/25057/1-oz-apmex-silver-rounds .
If all you are interested in Razz, is getting the most .999 silver for your money then your best bet would likely be to forgo all blobs altogether and just buy a product like this:
http://www.apmex.com/product/43773/25-kilo-bag-silver-grain-shot-9999-fine-peoles-803-75-oz
That product is actually .9999+ fine....so grab yourself a few bags of that to fill your sandbox with and let the rest of us enjoy our Momento Mori's and Chinese medals.
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