# Mass/Weight Units

A glossary of some of the mass/weight units found in the Metric, Troy, Apothecary, and Avoirdupois systems. Includes units that are no longer in use at this time.

Unit Name | Conversion Type | System | Note | Imperial/US | Metric |
---|---|---|---|---|---|

apothecaries units of mass | Mass/Weight | Apothecary | a system used by apothecaries in weighing out potions and medicines, abbreviated to ap | ||

assay ton (AT UK) | Mass/Weight | UK unit | 1 assay ton UK = 32.66667 grams proportionately represents 1 long ton = 32666.666677 troy ounces | 1 assay ton (AT UK) = 504.1 grains (gr) | 1 assay ton (AT UK) = 32.66667 grams (g) |

assay ton (AT US) | Mass/Weight | US Customary | 1 assay ton US = 29.16667 grams proportionately represents one short ton = 29166.66667 troy ounces | 1 assay ton (AT US) = 450.1 grains (gr) | 1 assay ton US = 29.16667 grams (g) |

avoirdupois units of mass | Mass/Weight | Avoirdupois | Avoirdupois is a traditional system of mass/weight in the Imperial and the US Customary systems, abbreviated to advp | ||

carat (ct) | Mass/Weight | Metric | a carat is a unit of mass used for weighing diamonds and other precious stones. One carat is equal to 10 points, 200 milligrams | 1 carat (ct) = 3.087 grains (gr) | 1 carat (ct) = 0.2 grams (g) |

centigram (cg) | Mass/Weight | Metric | unit of mass equal to 10 milligrams, one hundred of a gram | 1 centigram (cg) = 0.1543 grains (gr) | 1 centigram (cg) = 0.01 grams (g) |

decagram (dag) | Mass/Weight | Metric | the decagram a rarely used measure | 1 decagram (dag) = 154.3 grain (gr) | 1 decagram (dag) = 10 grams (g) |

decigram (dg) | Mass/Weight | Metric | SI unit of mass equal to one tenth of a gram | 1 decigram (dg) = 1.543 grains (gr) | 1 decigram (dg) = 0.1 grams (g) |

dram (dr advp) | Mass/Weight | Avoirdupois | the avoirdupois dram is 1/16th of an ounce (oz avdp) and 1/256th of a pound (lb avdp) | 1 dram (dr advp) = 27.344 grains (gr) | 1 dram (dr advp) = 1.7718 grams (g) |

dram (dr ap) | Mass/Weight | Apothecary | Unit in the apothecaries weight system equal to 1/8th ounce (oz ap) and 1/96th pound (lb ap) | 1 dram (dr ap) = 60 grains (gr) | 1 dram (dr ap) = 3.8879 grams (g) |

gamma (?) | Mass/Weight | Metric/old | one gamma is equal to one microgram | 1 gamma (?) = 0.0000154 grains (gr) | I gamma (y)= 0.000001 grams (g) |

grain (gr) | Mass/Weight | Avoirdupois/Troy/Apothecary | the grain is the same in avoirdupois, troy, and apothecaries units of mass | 1 grain (gr) = 0.05 scruple (s ap) | 1 grain (gr) = 0.0648 grams (g) |

gram (g) | Mass/Weight | Metric | SI unit of mass equal to one thousandth of a kilogram. | 1 gram (g) = 15.43 grains (gr) | 1 gram = 0.001 kilograms (kg) |

hectogram (hg) | Mass/Weight | Metric | SI unit of mass equal to one tenth of a kilogram | 1 hectogram (hg) = 0.22046 pounds (lb avdp) | 1 hectogram (hg) = 100 grams (g) |

hundredweight (cwt long) | Mass/Weight | Avoirdupois | The long hundred weight is equal to 1/20 long ton | 1 hundredweight (cwt long) = 112 pounds (lb avdp) | 1 hundredweight (cwt long) = 50.8 kilograms (kg) |

hundredweight (cwt short) | Mass/Weight | US Customary | The short hundred weight is equal to 1/20 short ton | 1 hundredweight (cwt short) = 100 pounds (lb avdp) | 1 hundredweight (cwt short)= 45.359 kilograms (kg) |

kilogram (kg) | Mass/Weight | Metric | The kilogram is a unit of weight, a measure in common usage throughout the world and the base unit in the International System of Units | 1 kilogram (kg) = 2.2046 pounds (lb avdp) | 1 kilogram (kg)= 1000 grams (g) |

metric unit of mass | Mass/Weight | Metric | weight system based on the decimal system. The modern name for the metric system is the SI, International System of Units with the kilogram as a mass base unit | ||

microgram (µg) | Mass/Weight | Metric | SI unit of mass equal to one millionth of a gram | 1 microgram (µg) = 0.0000154 grains (gr) | 1 microgram (µg) = 0.000001 grams (g) |

micropound (µlb) | Mass/Weight | Avoirdupois | the micropound is a small unit of avoirdupois weight and mass in the US and imperial systems | 1 micropound (µlb) = 0.007grains (gr) | 1 micropound (µlb) = 0.000454 grams (g) |

milligram (mg) | Mass/Weight | Metric | SI unit of mass equal to one thousandth of a gram | 1 milligram (mg) = 0.0154 grains (gr) | 1 milligram (mg) = 0.001 grams (g) |

nanogram (ng) | Mass/Weight | Metric | SI unit of mass equal to one billionth of a gram. | 1 nanogram (ng) = 0.0000000154 grains (gr) | 1 nanogram = 10e-9 grams (g) |

ounce (oz advp) | Mass/Weight | Avoirdupois | one ounce (oz advp) is uequal to 1/16th pound (lb avdp) | 1 ounce (oz advp) = 437.5 grains (gr) | 1 ounce (oz advp) = 28.3495 grams |

ounce (oz ap) | Mass/Weight | Apothecary | one ounce (oz ap) is equal to 1/12th pound (lb ap) | 1 ounce (oz ap) = 480 grains (gr) | 1 ounce (oz ap) = 31.103 grams (gr) |

ounce (oz tr) | Mass/Weight | Troy | one ounce (oz tr) is equal to 1/12th pound (lb tr) | 1 ounce (oz tr)= 480 grains (gr) | 1 ounce tr = 31.103 grams (gr) |

pennyweight (dwt) | Mass/Weight | Troy | the pennyweight (dwt ) is a unit of mass equal to , 1/20 th ounce (oz tr) , ?1/240 pound (lb tr) | 1 pennyweight (dwt) = 24 grains (gr) | 1 pennyweight (dwt) = 1.555 grams (g) |

point (pt) | Mass/Weight | metric | a unit of mass used for precious stones equalling one tenth of a carat | 1 point (pt) = 0.03086 grains (gr) | 1 point (pt) = 0.002 grams (g) |

pound (lb ap) | Mass/Weight | Apothecary | this pound is is the largest unit in the apothecaries weight system. one pound (tr and ap) = 12 ounces (tr or ap) | 1 pound (lb ap) = 5760 grains (gr) | 1 pound (lb ap) = 373.242 grams (g) |

pound (lb avdp) | Mass/Weight | Avoirdupois | unit of mass in the FPS system. The base unit of the avoirdupois, troy, and apothecaries sytems one pound (advp) 16 ounces (advp) | 1 pound (lb avdp)= 7000 grains (gr) | 1 pound (lb avdp)= 453.5 grams (g) |

pound (lb tr) | Mass/Weight | Troy | the Troy pound is the base unit of the Troy system of weights | 1 pound (lb tr) =5760 grains (gr) | 1 pound (lb tr) = 373.242 grams (g) |

quarter (qt long) | Mass/Weight | Avoirdupois | quarter (qt long)b is ased on one quarter of a long hundredweight | 1 quarter (qt long) = 28 pounds (lb advp) | 1 quarter (qt long) = 12.7 kilograms kg) |

quarter (qt short) | Mass/Weight | US Customary | quarter (qt short)based on one quarter of a short hundredweight | 1 quarter (qt short) = 25 pounds (lb advp) | 1 quarter short = 11.3398 kilograms (kg) |

scruple (s ap) | Mass/Weight | Apothecary | used by apothecaries - scrupulum, a small weight - scrupulus, small stone, pebble, dim of scrupus | 1 scruple (s ap) = 20 grains (gr) | 1 scruple (s ap) = 1.296 grams (g) |

stone (st) | Mass/Weight | Avoirdupois | traditional British unit of mass/weight equal to 14 avoirdupois pounds which is among others, used for expressing the weight of a person | 1stone (st) = 14 pounds (lb avdp) | 1 stone = 6.35 kilograms (kg) |

ton (long t) | Mass/Weight | Avoirdupois | long ton is the name off the ton used in the UK and sometimes known as the gross ton | 1 ton long = 2240 pound (lb avdp) | 1 ton long = 1016 kilograms (kg) |

ton (short tn) | Mass/Weight | US Customary | short ton is the standard ton used with in US Customary measures, sometimes known as the net ton | 1 ton (short tn) = 2000 pounds (lb avdp) | 1 ton (short tn) = 907.185 kilograms (kg) |

tonne (t) | Mass/Weight | Metric | metric unit of mass equal to one thousand kilograms known in North America as the metric ton | 1 tonne (t) = 0.984 ton (long t) and 1 tonne (t)= 1.102 (tn) short | 1 tonne (t) = 1000 kilograms (kg) |

troy units of mass | Mass/Weight | Troy | English weight system based on a troy pound of 5760 grains,Troy is abbreviated to tr |

#### Excavation

- Bulking/Swell Factors for Various Excavated/Mined Materials
- Swell and Shrink Percentages of Various Materials

#### Firewood

#### Lumber/Timber Volume

- Volume Conversions Table for Lumber/Timber Products
- Basic Specific Gravity of North American Trees / By Type (hardwood/softwood)
- The Basic Specific Gravity of Trees Listed by Region
- Basic Specific Gravity of North American Trees
- Specific Gravity of Australian Trees
- Basic Specific Gravity of European Trees
- Basic Specific Gravity of Indian Tree Species
- Shrinkage and Fibre Saturation point of Trees
- Specific Gravity and Shrinkage Values for Various Trees
- Timber/Lumber Volume Units