here's how I usually photograph my coin in macro. I'm using two lights set up one above and to the side of the coin. the above light is in a softbox while the one on the side is bare flash and this my kicker light.
here in this picture you can see my coins are not fully magnified just a close up of all the coins.
in this example I'm using now an extension tube on my dslr lens and as you can see it is much larger and fully magnified so you can see details on the coin.
the kicker light on the right illuminate the side and thus shows detail as well.
as if you are looking on a magnifying glass directly to the coin. - see the flattened tail of the six? that you can't see without using this macro technique.
like I said macro photography is my weakest, I was a little off in focus on this coin coz it is hard to get focus when your lens is too close to the subject and hand holding the camera.
I hope this example help you guys shoot your own find better. you don't need expensive flash you can do this also using table lamp. with practice you can get clearer shots. wait for your camera (point-in shoot) to fully focus before you pull the trigger.
know your camera's focus - the Auto Focus doesn't always get you to where you want your lens to focus so go over the manual it doesn't take you long to learn how to use it properly.
you can also apply this one when making video. see those youtube video? they showed you their finds but most often it was focused somewhere or blurry that is because the camera's Auto Focus point was looked on somewhere.
Happy Hunting and shooting your finds!