2006 Nevada state quarter struck on already struck dime

[Adamembry]

What would this be worth? I'm clueless

[Six Mile Rick]

.25c   Now I'm clueless too.

Wher's the dime?

[physics-fan3.14]

Show us the other side? 

I'd bet this is a "vise job" where a dime and a quarter were put together and, using some high pressure, the design of the dime was transferred to the quarter (could be a hammer, a hydraulic press, a really strong vise, or something like that). 

[BillJones]

If it were a quarter struck on a dime planchet you would have only a fraction of the design showing. This looks like a normal quarter to me taken from pocket change.