60x-100x is way to much you are looking for a lighted 30x pocket microscope.

That will not provide you the proper field of view to harvest on the average.
Zandor Reviewed by Zandor on . microscope I've never used one before is the one on this link what I need? RadioShack.com - Cables, Parts & Connectors: Tools & soldering equipment: Magnifiers: Illuminated Microscope Rating: 5