Making a lot of basins this month.  They all have the same features.  One Piece for the bottom and four or five pieces for the sides.  The angle of the side chages the overall shape of the basin.  Make the angle extreme and you get a  gold pan.  The black one is based on an original from the California Gold Fields.  The Bertrand basin is very similar to the Monticello sieve.  Just punch a bunch of holes in it and add handles.  The last one is a gold pan with a different kind of handle.  It has a rim all the way around the edge. This makes it more comfortable to hold when full of water.

If some one wanted a basin with a bottom that was larger than ten inches it would require a seam. As shown in the fourteen inch base the seam is on the right side.

Adding the seam makes the bottom uneven so the dots are added to make it lie flat.