As for the size of the claims you might want to have a look a the MNDM "Guide to Staking Mining Claims":

http://www.mndm.gov.on.ca/mndm/mines/lands/brochure/stminclm/guidstk_e.pdf

A mining claim is a square or rectangular area of

open Crown land or Crown mineral rights that a

licensed prospector marks out with a series of

claim posts and blazed lines. A claim can range

in size from 16 hectares (a 1-unit claim) to 256

hectares (a 16-unit claim).

The squares in the map represent a 16-unit claim and each side has a lenght of 1,6 kilometers (~ 1 mile).

 Hope that helps.

FANTOMAS