Trade Dollar 420 Grains Checker
Compare actual US trade-dollar mass to nominal420grains using1grain=0.06479891 gram. Caller verifies issue and tolerance; not composition or authentication and wear/loss remain.
Description
Coin mass can be compared with the nominal standard of an independently identified issue.
Coin mass can be compared with the nominal standard of an independently identified issue.1
This checker uses the original Trade dollar’s 420-grain standard and a tolerance you supply.
When to use Trade Dollar 420 Grains Checker
Use this tool to calculate or review the supplied observations under the stated rules. Establish the coin issue, source edition, measurement basis and reference date where applicable.
How to use Trade Dollar 420 Grains Checker and understand its results
- Establish the coin issue, source edition, measurement basis and reference date where applicable.
- Enter observedMassGrams, callerApplicableToleranceGrams, using the field meanings and rules below, then run the tool.
- Read result. Inspect nested result fields where present, and review unknown records separately from known matches.
- Correct any reported input issue and run again. Before using a successful result, check the stated units, signs, reference scope and observation coverage.
| Input field | Meaning | Value type | Requirement |
|---|---|---|---|
| observedMassGrams | Observed mass grams | number | Required |
| callerApplicableToleranceGrams | Caller applicable tolerance grams | number | Required |
Require positive observed grams and nonnegative tolerance grams. Convert 420 grains with exactly .06479891 grams per grain, subtract the nominal grams from observed mass, and test absolute difference≤tolerance. Boundaries pass inclusively.
nominal=420×.06479891; within=|observed−nominal|≤tolerance Use the matching field units and the exact boundary, ordering and reference rules above.
| Output field | Meaning | Value type |
|---|---|---|
| result | Calculated observation or qualified reference | object |
| result.nominal420GrainsGrams | nominal420 Grains Grams | number |
| result.signedMassDifferenceGrams | signed Mass Difference Grams; preserve the subtraction order and sign defined in the mechanics | number |
| result.withinCallerMassTolerance | within Caller Mass Tolerance | boolean |
{
"input": {
"observedMassGrams": 27.216,
"callerApplicableToleranceGrams": 0.01
},
"output": {
"result": {
"nominal420GrainsGrams": 27.2155422,
"signedMassDifferenceGrams": 0.0004577999999995086,
"withinCallerMassTolerance": true
}
}
}Limitations and assumptions
Coin identification, reference applicability and measurement uncertainty require separate evidence. A returned explanation or arithmetic agreement does not establish authenticity, a certified grade or a current market value.
Missing required fields, unknown fields, wrong types and violated rules return input issues. Numeric values and outputs must be finite. Extremely large composite outputs are rejected.
Alternative or Complementary methods
For a related step, use Morgan Peace Weight Checker: Original Morgan and Peace silver dollars have a nominal mass that can be compared with a measurement. For a complementary comparison, use Tolerance Band Compliance Checker: A tolerance band has both lower and upper limits, which can differ from a symmetric nominal tolerance.
References
-
Trade Dollar 420 Grains Checker — tool.io
Similar or alternative tools
- Morgan Peace Weight Checker
Original Morgan and Peace silver dollars have a nominal mass that can be compared with a measurement.
- Tolerance Band Compliance Checker
A tolerance band has both lower and upper limits, which can differ from a symmetric nominal tolerance.