CUTTING AND FASHIONING PRECIOUS STONES.
Very few
precious stones, as we receive them from the hands of nature, present
the beautiful qualities for which we look in these concentrated
treasures of the earth. Often they are waterworn pebbles, roughened by
attrition and blows during years or even centuries of wanderings in the
beds of streams and rivers. If we find them intact in their rocky
homes, they are oft-times obscured with flaws and intruding matters
which mar their beauty. If transparent and without speck or fracture,
yet the natural forms in which crystallised gem-stones occur are but
rarely adapted for direct employment in objects of jewellery. In shape
or size they are awkward for such use, while many of those marvellous
optical qualities which distinguish them from the crowd of commoner
materials are brought into prominence only by the artificial processes
of cutting and polishing. These processes convert rough crystals into
shapely gems, having fine qualities of surface lustre and interior
colour, and, withal, much less liable to fracture than the original
stone. Now and then a perfect natural octohedron of flawless diamond or
rosy spinel may be set in a ring or jewel ; but such instances are
exceptional, and gem-stones, in order that all their elements of beauty
may be developed to the uttermost, must be cut and polished according
to rule.
All the different forms into which precious stones are cut may
