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Convert Pennyweight to Obolus (dwt to ob) instantly with accurate, readable results.
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Pennyweight (dwt) — a troy unit of mass for precious metals
It is defined as exactly 24 grains, or one twentieth of a troy ounce. Used mainly for measuring precious metals, jewelry, gemstones, dental alloys, and historical coin or bullion weights.
- Symbol: dwt
- System: Troy unit for mass
- Exact relations: 1 dwt = 24 gr = 1/20 oz t = 1.55517384 g
- Metric equivalents: 1 dwt = 1.55517384 g ≈ 0.00155517 kg
- Typical examples: small gold jewelry may weigh a few dwt; precious-metal scrap is often priced per dwt; 20 dwt equals 1 troy ounce.
Obolus (obol) — a historical unit of mass equal to 10 grains
It is commonly treated as half a scruple, or 10 grains, in historical Roman and apothecaries’ weight contexts; because the obolus was also a coin and ancient weight term, its exact value can vary by period and region. Used mainly in historical medicine, pharmacy, numismatics, and references to ancient or apothecaries’ measures.
- Symbol: obol, obolus
- System: Historical Roman and apothecaries’ unit for mass
- Exact relations: 1 obolus = 1/2 scruple = 10 gr = 647.9891 mg
- Metric equivalents: 1 obolus = 0.6479891 g ≈ 0.000647989 kg
- Typical examples: historical prescriptions may mention oboli; 2 oboli equals scruple; 1 obolus is a little less than 2/3 of a gram.