I have four $10 strikes with all saying on one side "Hard Rock Hotel" on the silver part. On the bronze part it says "IN ROCK WE TRUST LAS VEGAS, NV". On the other side of one of the strikes it says "H R" with rays coming out of it. The other strike has "sports Delux Lounge" and has pictures of two dolphins crossing each other. The other coin has words "Mr. Lucky's = 24/7 on it. And the last one has words "THE JOINT" with an ace of spades and what looks like fire coming out of both sides of the ace of spades. My question is that it doesn't say anywhere that it is clad or .999 silver. I have heard that there are some strikes that don't have any indication of it being silver when it is. Can you guys help me identify this metal and if they are truly silver? Thanks.