Offered here are Twenty-Two original round brass sieves set within the original brass container that would have seen use as a Field Method of determining the grain size in an ore sample by a wandering Prospector or Assayers. Sieves measure 2.0" diameter in varying sieve sizes and stamped Pierres and the number for the sieve. The brass container measures 1.25" high, with the sieves being held in place with an inside lip edge. A rare display piece of Prospecting and Mining history tough to find outside of collections. Thanks for looking!