DESCRIPTION:

GEM TYPE: TOUCHSTONE BEAD, HOLE DRILLED FOR NECKLACE.

WEIGHT: 17.10 CARATS

SIZE: 24 X 13 X 10 MM

COLOUR:  BLACK

CLARITY: OPAQUE

1 PIECE

ADDITIONAL COMMENT:

A TOUCHSTONE IS A SMALL TABLET OF DARK STONE SUCH AS FIELDSTONE, SLATE OR LYDITE, USED FOR

ASSAYING PRECIOUS METAL ALLOYS. IT HAS A FINELY GRAINED SURFACE ON WHICH SOFT METALS LEAVE A

VISIBLE TRACE.

DRAWING A LINE WITH THE GOLD ON THE TOUCHSTONE WILL LEAVE A VISIBLE TRACE. THE TRACE WILL

REACT DIFFERENTLY TO SPECIFIC CONCENTRATION OF NITRIC ACID, THEREBY IDENTIFYING THE QUALITY

OF THE GOLD. THUS 18 CT PURITY IS NOT AFFECTED BUT 14 CT GOLD WILL SHOW CHEMICAL ACTIVITY.