This might help:
http://www.bjdecastro.com/art-blog/2005/08/how-to-tell-if-it-is-an-original-reproduction-or-print/.
If it's a print from a wood block, then you will have multiple layers of paint pressed on top of each other (one layer for each color, lightest to darkest). They are likely to overlap as the block is covered in one color, pressed on the paper, then carved more, covered in a different color, pressed, etc... until done [or at least that's the way I've done it in the past].
One good way to tell that it's an original block print, is if some of the colors are evident underneath each other, if the paint is thickest on the darkest parts, and/or the paper was slightly misaligned - check the edges of the figures with a magnifying glass to see if there are lines of paint of one color.
I like the suggestion from the article above to look for 'dots' from a reproduction company vs the paint that would come from a block print. I had never thought of that. Although, I have to admit, that if either the reproduction or block printing were done very well, it could be hard to tell without an appraiser.
Hope this helps!
