Carats to Stones

Stones to Carats (Swap Units)


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Carats to Stones formula

st =
ct * 0.000031495
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More information: Stones


Abbreviated "ct." and spelled with a "c" is a measure of weight used for gemstones. One carat is equal to 1/5 of a gram (200 milligrams). Stones are measured to the nearest hundredth of a carat. A hundreth of a carat is also called a point. Thus a .10 carat stone can be called either 10 points, or 1/10 of a carat. Small stones like .05, and .10ct are most often referred to by point designations. Note that karat with a "K" is a measure of the purity of a gold alloy. A one carat round diamond of average proportions is approximately 6.5mm in diameter. Note that this relationship of weight and size is different for each family of stones. For example ruby and sapphire are both heavier than diamond (technically, they have a higher specific gravity, so a 1 carat ruby or sapphire is smaller in size than a on carat diamond. See Weights and Measures of Gold, Silver and Precious Gems for more information.


Carats to Stones formula

st =
ct * 0.000031495


The stone is a unit of weight in the imperial system used informally in the UK and Ireland, almost exclusively as a measure of body weight. Although sanctioned by the EU for use as a supplementary unit it is essentially obsolete outside the UK and Ireland.


Carats to Stones table

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Carats Stones
0ct 0.00st
1ct 0.00st
2ct 0.00st
3ct 0.00st
4ct 0.00st
5ct 0.00st
6ct 0.00st
7ct 0.00st
8ct 0.00st
9ct 0.00st
10ct 0.00st
11ct 0.00st
12ct 0.00st
13ct 0.00st
14ct 0.00st
15ct 0.00st
16ct 0.00st
17ct 0.00st
18ct 0.00st
19ct 0.00st
Carats Stones
20ct 0.00st
21ct 0.00st
22ct 0.00st
23ct 0.00st
24ct 0.00st
25ct 0.00st
26ct 0.00st
27ct 0.00st
28ct 0.00st
29ct 0.00st
30ct 0.00st
31ct 0.00st
32ct 0.00st
33ct 0.00st
34ct 0.00st
35ct 0.00st
36ct 0.00st
37ct 0.00st
38ct 0.00st
39ct 0.00st
Carats Stones
40ct 0.00st
41ct 0.00st
42ct 0.00st
43ct 0.00st
44ct 0.00st
45ct 0.00st
46ct 0.00st
47ct 0.00st
48ct 0.00st
49ct 0.00st
50ct 0.00st
51ct 0.00st
52ct 0.00st
53ct 0.00st
54ct 0.00st
55ct 0.00st
56ct 0.00st
57ct 0.00st
58ct 0.00st
59ct 0.00st