RE: rock samplesAssay ton (abbreviation 'AT') is not a unit of measurement, but a standard quantity used in assaying ores of precious metals; it is 29 1⁄6 grams (short assay ton) or 32 2⁄3 grams (long assay ton), the amount which bears the same ratio to a milligram as a short or long ton bears to a troy ounce. In other words, the number of milligrams of a particular metal found in a sample of this size gives the number of troy ounces contained in a short or long ton of ore.
o there can be misleading indicators to the positive or negative. I theory one would grid out a one ton sample location and the 291/2 grams (short ton) or 32 2/3 grams (lond eaassay ton) sample bagged could derive frim a quartz hit of visible gold. Take the visible go frims this gid of a ton and the long assay ton bagged could show over quanity for AU/T. However, the ajacent ton could show over levels, So it is a misleading indicator but a place to start. An important place to start.
I trust this answered you question clearly.
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