Is This Real Silver?

So my uncle was a long time silver collector. he gave me about 20 ounces of silver eagles...one, however, is a bit peculiar.

First off, its a medallion. Meaning it has the silver eagle design, but it has no value. Basically its a silver eagle round, rather than a coin.

Its graded, PR70, by PCI, and has the words "classic coin series" on it. its mintage is 1000.

Heres where I am a bit confused.

On the back it says .999 silver. Its once ounce.

However, it also says "100 mil."

Now, I'm trying to figure out whether its genuine silver - you know, the valuable kind on ebay. Or if its 100 MILS silver.

I just find it peculiar because its graded by a reputable coin grading service, PR70, Deep cameo, and has a mintage of 1000. It also, once again, says .999 silver. Its 1 oz

The thing that is confusing me is the "100 mil."

Is there anything else this 100 mil could mean?