Regarding non-metric mass. More proof of the superiority of the metric system.

Metric

A gram was initially standardized as 1 cm3 of water at 101.325 KPa = 1 atm, and its densest temperature (ca. 4 C).

• 1 metric ton = 1 tonne = 1000 Kg ~ 2204.62262 pounds
• 1 Kg = 2 metric pounds = 1000 g ~ 2.20462262 avoirdupois pounds ~ 35.27396193958 avoirdupois ounces ~ 2.6792 troy pounds ~ 32.151 troy ounces
• 1 metric pound = 500 g ~ 1.10231131 avoirdupois pounds ~ 1.3396 troy pounds
• 1g = 5 carats ~ 15.432 grains
• 1 carat = 200 mg. Note that "karat" refers to 1/24 purity: 24 * (mass of gold in object / mass of object). Hence 24 karat is 100% gold, but 12 karat is 50%.

Avoirdupois

The avoirdupois weight system is used by the USS (U.S. System) and the British IS (Imperial System). The word avoirdupois is derived from the Old French for "goods of weight" (as opposed to goods sold by the piece). The avoirdupois is the default or international pound.

The original avoirdupois had these units and are used by the USS.

• 1 [short] ton = 20 [short] cwt (hundredweights) = 80 [short] quarters = 2000 pounds = 907.18474 Kg
• 1 [short] cwt = 4 [short] quarters = 100 pounds = 1600 ounces = 45.359237 Kg
• 1 [short] quarter = 25 pounds = 400 ounces = 11.33980925 Kg
• 1 pound = 16 ounces = 0.45359237 Kg = 453.59237 g
• 1 ounce = 0.028349523125 Kg = 28.349523125 g

The IS was modified around the "stone" unit:

• 1 [long] ton = 20 UK cwt = 80 [long] quarters = 160 stone = 2240 pounds = 1016.0469088 Kg
• 1 [long] cwt = 4 [long] quarters = 8 stone = 112 pounds = 50.80234544 Kg
• 1 [long] quarter = 2 stone = 28 pounds = 12.70058636 Kg
• 1 stone = 14 pounds = 6.35029318 Kg
• 1 pound =  16 ounces = 0.45359237 Kg = 453.59237 g
• 1 ounce = 0.028349523125 = 28.349523125 g

Troy and Apothecary

The troy weight system is used for precious metals and gems. It is named after Troyes, France, an important city of trade during the Middle Ages. It is independent of other systems of measurement such as metric (SI), American (USS), or British (IS).

• 1 troy pound = 12 troy ounces = 240 pennyweights = 288 scruples = 5760 grain = 0.373241722 Kg = 373.2417216 g
• 1 troy ounce = 20 pennyweights = 480 grains = 31.1034768 g
• 1 pennyweight = 24 grains = 1.55517384 g
• 1 grain = 0.06479891 g

Note that a troy ounce > avoirdupois ounce, but a troy pound < avoirdupois pound.

The apothecaries' mass system was used by pharmacists and chemists. The apothecaries' system has the same troy pound and troy ounces but then subdivides differently.

• 1 troy/apothecary pound = 12 troy/apothecary ounces = 96 dram (drachms) = 288 scruples = 5760 grain = 0.373241722 Kg = 373.241722 g
• 1 troy/apothecary ounce = 8 drams (drachms) = 24 scruples = 480 grains = 31.1034768 g
• 1 dram (drachm) = 3 scruples = 60 grains = 3.8879346 g
• 1 scruple = 20 grains = 1.2959782 g
• 1 grain = 0.06479891 g

Page Modified: (Hand noted: ) (Auto noted: )