March 3, 1888 - John Miller explains how to measure quartz

“HOW TO MEASURE QUARTZ.

The following appeared in a recent number of the Otago Witness :~Stope asks: (1) How can I measure quartz in the win or lode? (2) What measurement goes to the ton in the vein? (3) How can I measure quartz in the paddock — that is, broken quartz? (4) What measurement in the paddock goes to the ton ?

— We have submitted your queries to Mr JA. Miller, of Arrowtown, who replies as follows (1) Multiply the width of the shoot of quartz by the depth, and the result again by the thickness of the lode; the result will be the cubic contents of the quartz. Example : Say a shoot has been proved to a depth of 60ft and is 80ft wide, the stone being 2 1/2 ft thick. Then 60 x 80 ==1800 x 2 1/2 =12,000 cubic feet, or 4000 cubic yards. (2) In the vein half a cubic yard, or 13 1/2 cubic feet, may be allowed to a ton weight. Molesworth gives the weight of a cubic yard of quartz at 41cwt, or 4592lb per cubic yard. Rankin allows 165lb to a cubic foot of quartz, or 455lb (?) per cubic yard. All quartz, however, varies much in weight, according as it is drossy or dense. (3) This question is difficult to answer, as the necessary calculation depends upon the shape of the paddock. To proceed you must ascertain the three dimensions of your paddocks— that is, its length, width, and depth — and multiply these sums as in the above example; but observe that all the measurements must be made at right angles to the base of your calculation. To keep tally of the quartz in your paddock it is always better plan to ascertain how much quartz your truck holds, and then keep an account of the number of trucks emptied into the paddock. (4) A cubic yard of broken quartz is generally allowed to weigh a ton, though in practice it will be found to be often a great deal heavier.”

Source: TE AROHA NEWS, VOLUME V, ISSUE 244, 3 MARCH 1888, PAGE 2 (https://paperspast.natlib.govt.nz/newspapers/TAN18880303.2.15)