.999 fine silver, yes.

These are Bitcoin Specie, from the Bitcoin Specie Project.
We are working on the gold versions as well as different sizes of the silver.  Please expect these shortly.
There is a more detailed explanation of the goals of the Project at the link in my sig, but the essence of it is to create a useful pocket change for Bitcoin.
There is no bitcoin stored in them (in the same way that there are no dollars stored within silver dollars)
The value does fluctuate with the prices of silver and bitcoin and is continuously available at Coldhardca.sh (that is where the QR on the specie silver piece takes you).  The premium over silver is also listed there and you can see by changing the quantity that it decreases.  This is to encourage distribution for those that buy in high quantity and sell or use in small quantity.  This activity is rewarded by its pricing mechanism.
Pricing is competitive with the national pieces such as Silver Eagles, but our quality is higher, and they are more collectible.

In the endgame, we will contend with many issues.  One of these is the volume of transactions hitting the block chain.  The block chain is an expense to bitcoin.  Use of pocket change for small in person payments as an off block-chain transaction helps to reduce the cost of the bitcoin currency.

Additionally, these are purely anonymous and not pseudononymous.  Cash and carry type transactions can be easily facilitated with them as a store of value.

Also in the endgame, our expectation is that bitcoin will not have the volatility that it has currently, increasing the utility of these.

The project started last year at the Spring Bitcoin Foundation conference and so is only a year old.  It is not profitable (there are still too few bitcoin folks, and too spread out).  Nevertheless, we will persist in the effort and welcome those who would join the project.  There are many opportunities.

Beware, there are some counterfeits but they are easy to distinguish if you know what to look for (the one pictured is not a counterfeit).