GEMSTONES
DEFINITION MINERALS that are cut RARE= valuable Usually above 7 on hardness scale
Gold Pure gold is soft (malleable), heavy and expensive! Gold in jewelry is an alloy (mix of metals) K= % of gold 24K= 100% gold 14K = ?
The 5 C’s Cut Clarity Color Carat Cost
CUT Ground down on a grinding wheel Faceting- for TLT-TPT Lets light through mineral; adds brilliance Cabachoning- for OPQ
Diamonds in the “rough”
Round brilliant
Faceting
Cabachoning
Cabachons
Clarity Amount of imperfections Specs Cracks discoloration
Color Colored gems= deep color, more $$ Diamonds= D-Z scale (see handout) Exception is Z+ fancy diamonds are colored diamonds- most rare of all
D, Fl I 3
Fancy Diamonds More rare than traditional diamonds.
Carat Weight of gemstone 1 ct= 200 mg 100 pts.= 1 carat TGW= total gem weight for many stones together
Cost Depends on previous 4 C’s
FAMOUS DIAMONDS
CULLINIAN 9
CULLINAN I STAR OF AFRICA 530 CTS.
Cullinan II: 317 cts.
Kohinoor Originally 186 cts. Now 108 cts. Queen of England
HOPE DIAMOND; 65 cts. New setting Nov. 2010
Smithsonian
Tiffany yellow
PINK SUNRISE 30 CTS.
DeYoung Red 5.03 cts.
Taylor-Burton Diamond 68 cts.
Smithsonian diamonds
MILLENIUM STAR- 230 CTS D, IF (“Millenniums come and go, but a diamond is forever” DeBeers
The Regent Diamond 410 carat diamond when originally found. The Regent Diamond 410 carat diamond when originally found. Later cut down to 140 carats. Today is at The Louvre.
Birthstones
Garnet January birthstone
ALEXANDRITE 1.6 ct $16,000
OPAL (hydrated quartz)
TOPAZ November birthstone
Emerald May birthstone
Peridot August Birthstone
Synthetic gemstones Advantages? Disadvantages? Less expensive Less flawed Disadvantages?