Appears to be a posthumous silver drachm of his from Lampsakos. I would expect the weight to be close to 4 grams. Edit: Not uncommon for these to fetch $100, the weight is an important factor.
How did you come to be in possession of these coins? A relative? Appears genuine, but nicer pictures would be a plus. This one could be worth something. PS: We give sizes in millimeter for coins, and weight in grams. Inches makes it too confusing.
my boss has a collection of items she has acquired over the years from estate sales all over the country. i found a box of foreign money, paper and lots of coins. i went through them and found the ones i thought to be perhaps valuable.
3.0 is too light to be an official drachm. The other thing to look for as @Theodosius suggests if there is a casting seam. Would like something like this, but maybe less pronounced. If it has a seam the value is zero.
I believe David is correct and the value about right. Although I can't offer any opinion about genuineness.
Yes it is too light and worth 0. Seams can be razor thin. http://www.forumancientcoins.com/fakes/displayimage.php?album=search&cat=0&pos=3
If they were just the same dies that would not be worrying. Even with coins as common as those of Alexander you see die matches if you look closely at enough coins. In this case however, both coins are cast twins of the same host coin, no doubt about it.