In 1976 two issues of the Ike were made. There was a copper-nickel issue and a silver issue. If you had one of each it would be very easy to tell them appart. The copper-nickel clad coin will have a copper colored band around the edge. That would be a dead give away that it is a clad coin and it would also have a nickel color, not a silver color - like a clad Kennedy half dollar for example. The silver issue will have a solid silver band around the edge and have a white silvery color. The silver issue has .3161 oz. Pure silver, roughly 1/3 oz silver. Unfortunately, neither the clad or the silver Ike is worth very much. If the coin is silver, it may be worth $12 - $30 depending on condition. The clad version maybe $6 - $8 depending on condition. Still worth holding on to. If you familiar with Ebay you can check out my store and guides on related topics.
Two ways actually I'm no expert or anything but if you take another dollar and drop both of them it will sound fake or a lighter ting than one that has more ingredients. Or let it sit out in a room for a couple of days and see if it starts to tarnish where you have touched it your natural oils will also cause it to tarnish.
From how I've been told, the Bi-Ikes are Type 1 silver, The one dollar is in bold letters and the Type 2 clad are not in bold letters. I believe this to be true with all the Ike dollars. 1973 is the key dollar and the 1990 Ike centennial, Crown jewel.