Using Euro coins as weights (2004)
Coins emerge as surprisingly practical, standardized weights for everyday measurement and calibration, from Euro cents and US nickels to Soviet and Japanese coins intentionally designed to match simple gram values. Commenters share uses ranging from DIY balance scales, drug and coffee weighing, and weighted vests to coin-counting in retail, while debating limitations from wear, precision needs, and alternatives like sand or commercial plates. The conversation also touches on how coin design, seigniorage, and the shift from commodity to fiat money link physical weight to broader questions about the nature and trustworthiness of currency.
Coins as Convenient Physical Standards
- Many comments note coins are mass‑produced with tight tolerances, making them handy approximate weights and length gauges.
- Examples: euro cent stacks for grams; copper euro cents are all ~1.67 mm thick; US nickel ≈ 5 g; British 20p = 5 g; 1 JPY coin and US bills ≈ 1 g; 1 SEK = 7 g; Australian $1 = 9 g.
- Several currencies have systematic designs:
- Soviet kopecks (1, 2, 3, 5) weighed their face value in grams and had simple diameters.
- British coins have rough proportionalities by value within groups (e.g., 1p/2p, 5p/10p).
- US dime/quarter/half/dollar have neat weight relationships (e.g., each $20/lb).
Practical Uses and Hacks
- Coins used to:
- Calibrate cheap pocket or coffee scales (nickels; euro cents).
- Provide reference areas in computer vision.
- Build improvised balances from Lego.
- Weigh drugs in school.
- One person uses ~15 kg of euro cents as load in a weighted vest, acquired at face value from the central bank. Others mention pre‑rolled bank coin wrappers for neat “weight modules.”
- Beach sand is suggested as free ballast, but others note containment hassles and legal/environmental limits on removing sand.
Accuracy, Wear, and Limitations
- Debate over coin wear: some report almost no meaningful wear; others have coins with edges worn smooth and say that’s unacceptable as calibration standards.
- Consensus: fine for low‑precision needs; not suitable for analytical‑grade measurement.
- Water as a volume‑based mass standard is discussed; variability with temperature, salinity, etc., makes it unsuitable for very high precision.
Exercise with Weights
- Thread diverges into weighted vests and limb weights.
- Opinions split: some warn about joint strain and injury risk; others report safe use when weight is modest and progression is gradual.
- Limb weights are considered riskier than vests due to leverage and momentum on joints.
Money, Weight, and Monetary Systems
- Several remarks link currency names (pound, peso, shekel, penny, dime, quarter) to origins in weight or subdivisions.
- Historical context: coins once embodied metal value; debasement and the shift to fiat are discussed, along with inflation and inequality debates.
- A long subthread explores fiat vs commodity money, central‑bank policy, multiple currency types for different transaction classes, and seigniorage as a proxy for trust.