The red stone is a very rare and beautiful form of jasper;
the white stone is chalcedony;
the yellow stone is carnelian agate;
the black stone is obsidian;
the center stone is gem green variscite with spider-web matrix.
These particular pieces are shown as examples only, since they were custom-made to order, but I can make a similar one for you.
Prices start at $225.00, depending on the size and gemstones used.