Divide the recovered-mass reading in grams by the actual processed volume in liters to record observed g/L. For example, 0.02 g from 10 L gives 0.002 g/L. This describes those entered measurements. It does not establish a deposit’s grade, how much gold escaped the pan, or what another sample will contain.

The working log above keeps each independent sample, its measurement conditions and its unresolved limits. No field trip, gold assay, scale calibration or product test was performed for this guide. The examples are arithmetic, not reported finds.

Keep the denominator consistent

Choose whether the measured volume is original bulk material before classification or the classified fraction actually processed. Use the same basis throughout one log. A comparison between those two denominators would answer different questions, even if both results used g/L.

Record the actual volume represented by the recovered material. A nominal bucket capacity or a count of partly filled pans does not supply that measurement. Keep reprocessing of the same sample in its notes; do not add it as a second independent sample and count its original volume again. Start another log when the volume basis or processing method changes.

For panning movements, use the beginner panning guide . The fine-gold cleanup guide covers the separate task of finishing concentrates. This log records your observations; it does not identify shiny material or turn a mixed concentrate’s weight into gold mass.

Record the scale limit with the reading

Enter the numerical mass reading separately from the scale’s stated resolution. NIST’s resolution guidance explains that displayed digits do not establish a measurement system’s actual resolution and that stated resolution needs checking under real measurement conditions. This calculator does not perform that check.

An entered 0.001 g with a stated 0.01 g resolution stays approximate. A zero reading stays a zero display, rather than proof that the sample contained no gold. If the result was only reported as below resolution, select that non-numeric status; the tool supplies no invented mass, ratio or upper detection bound. Leave an unweighed sample’s mass unknown.

NIST’s weighing FAQ distinguishes scale division from accuracy classification and explains the role of tare in a net reading. Record the instrument, container/tare handling, material identification and conditions with each sample. A resolution entry alone is not a calibration, purity measurement or complete uncertainty estimate.

Read the median, range and pooled ratio separately

Only rows with a positive known volume and a numerical mass reading contribute to the summaries. Excluded records contribute neither their mass nor their volume. Approximate, zero and unknown-resolution numerical readings remain visibly counted and flagged; the arithmetic does not improve their accuracy.

Arithmetic example Processed volume Mass reading Observed ratio
Example A 10 L 0.02 g 0.002 g/L
Example B 20 L 0.06 g 0.003 g/L

The entered ratios range from 0.002 to 0.003 g/L. Their median is 0.0025 g/L. As NIST defines the median , two middle values are averaged when the count is even. The pooled ratio instead divides the matched 0.08 g by 30 L, giving approximately 0.002667 g/L. It gives larger-volume rows more influence. Neither statistic establishes geological representativeness or recovery efficiency.

Take a field record and keep a copy

Record What to keep
Sample identity Unique ID and known date
Processed material Actual volume, basis and processing method
Result Numerical reading, below-resolution report or not weighed
Measurement limits Stated scale resolution, instrument and conditions
Context Material identification, repeat processing and useful field notes

The log supports up to 100 records. Add or update an entry before exporting; an unsaved edit disables export so it cannot silently print an older value. CSV and print retain the actual records, matched-row summaries and limitations. There is no automatic saving or server calculation, so download before closing the tab. Exact coordinates are not required.

The guides library provides the next reading path. Confirm access separately using the mining-claim and permit guide . No permission, reserve, earnings, future-yield or percentage-recovery result is produced here.

Method and sources

We checked the following primary guidance on October 16, 2026 and built the reproducible arithmetic above. The log summarizes reader entries; it does not validate sample selection, gold identity, instrument performance or field conditions.