Carats	Percentage	Millesimal	Coins	Comments
24	100%	1000	None*	Probably Only Exists in Theory
23.9976	99.999%	999.99	Canadian $350, & New 5 9's Maples	Somewhat Pointless
23.976	99.99%	999.9	Australian Nuggets, Philharmonikers, Buffalos, 1983 - 2006 Maples	Most Electrolytically Refined Gold Qualifies
23.976	99.9%	999	1979 - 1982 Maples
23.88	99.5%	995	London Good Delivery Bars
23.76	99%	99.9	None
22	91.66%	916.6	Sovereigns, Krugerrands, US Gold Bullion Eagles
21.6	90%	900	US Eagles, Napoleons, Vrenelli, Marenghi	Coinage Gold
18	75%	750	None	Excellent for Jewellery
15	62.5%	625	None	Old Jewellery Standard
14	58.33%	583.3	None	Not as Good as 18ct, Not as Cheap as 10kt
12	50%	500	None	Half and Half
10KP	41.66%	416.6	None	Used for Cheap American Jewellery
10*	39.58%	395.8	None	Used for Cheap American Jewellery
9	37.5%	375	None	Used for Cheap British Jewellery

Notes
Carat = Karats
Millesimal = Parts per thousand.
Coins = Best known examples, see our "Contents" page for more complete list.
None* = About as likely as an honest politician
10KP = American 10 karat "plumb", i.e. real actual 10carat gold.
10* = American minimum legal standard for 10 karat, which is actually only 9.5 karat.

USA Karat Gold Alloys
All US karat alloys can legally be a half carat (2.0833%) lower than stated!

22 Carat v 24 Carat
A discussion about 22 carat versus "24 carat" gold bullion coins, with regard to investment.

Low Carat Gold Alloys
A discussion of the merits and demerits of low carat gold alloy coins.