I like the look of "striations" on coins (sometimes called "die finishing lines"). These are tiny, raised marks left on coins from coining dies that have been "polished," or from planchets that have been burnished, leaving incuse marks. I think that's how it works... Here are is a 1968 South Korean 5 Won coin
I don't recall any particularly noticeable striations on any of my coins, but I've always liked that "dragon boat" design on those 5-won pieces, and I like your photos.
