toy glass marbles

Toy Glass Marbles imported from Mexico.  They are marbled with bright swirling colors and most varieties are opaque.  (Refer to photo.)  The marbles are spherical, not flat like glass gems, and the nominal size is 16mm (9/16 inch).  Why do we sell these for mosaic applications?  Because they have beautiful swirled colors that you just can't seem to find in craft gems.  The marbles can easily be used in mosaic stepping stones and other applications where the pieces are pressed into wet concrete, although the marbles should be pressed in securely flush with the surface and not used in excess quantities so that they create a slip hazzard.  Gluing marbles to a flat surface requires more care.  You should use a thick and tarry adhesive like Liquid Nails brand so that the marbles don't slip out during grouting or perhaps consider using thinset bonding mortar (from a building material store) instead of glue.  Some people report that they place the marbles in an old towel and crack with a hammer and use the pieces, but the pieces can be quite sharp.