Does the alpha not have a tid Number display? I thought all the frat bros gave an id number. On the Omega everything between 1-40 is Iron, 40-50 is foil, 50-60 is pull tabs, 60-70 screwcaps, 70-80 zinc pennies, 80-90 dimes, 90+ quarters and silver. at least that is what the manual says they are supposed to be. Foil almost always is 50-52, nickels usually come in at 57, pull tabs vary from 55 all the way up to 65 with the most common being 60-62, zincs are almost always 78-79 although a few badly corroded ones come in lower. Dimes pop at 84-85, quarters 91-92 and screwcaps 94-99. I did try it out on a silver dollar that came in at 99 all the way out to the point it would no longer pick it up. My heavy 14k ring comes in at 67 so right between pull tab and zinc cent, the small one I dug came in at a 62 But to be fair it was residing an inch from a pull tab so it may have come in lower all by itself. Hopefully the bounty hunter coil will work fine for you, be carefull if you use zipties to leave enough slack for the head to rotate. I originally zip tied my wire to the stem then thought that might have caused the problem, so I ended up with a couple more velcro loops to hold the wire. If the bounty hunter coils will work on your detector Ive heard good things about the 4" nugget coil, about 34$ on amazon for working in trashy areas. I was going to buy one for the lone star before I bit the bullet and bought the omega.