How Well Do You Know Your World Coins?

33... 1933 French 20 francs?

61 Indonesia 50 sen
79 Indonesia too, 5 or 10 rupiah

And for 82 - India 20 paise and I hope we are through!

It was a pleasure. Thanks for setting this identification-contest up!

Indeed, but coin quality control in India is non-existing, I think. Many coins are struck that bad they didn't resemble your good picture.

Go ahead, I'd say. A different perspective (dates from different coins) or take on the idea (different aspect, not dates but other common devices or details) would certainly be interesting to see.

Coats of arms are perhaps not the best choice, as Krause world catalogs have their picture lists. So, anyone with a Krause catalog would get all/most.

On the other hand, since you mentioned eagles - let's take eagles' heads, for example. They may not be that instantly identifiable, especially since styles varied within a single country.

There are many other possibilites for similar threads:
- dates (crop the dates so that only the first two digits are visible. So, if you took coins from the 20th century only, you'd have a set of 100 images all reading "19")
- dates (exactly like this one but from the 19th century. Which would include German states)
- face values (all different or all the same), etc.
Practically anything large enough to be recognizable but small enough so that Google doesn't recognize it.

The aforementioned eagles' heads are different from all these is one way - that they are not digits or lettering. I wonder how that would affect the difficulty.