Processing the Ore
Ore from the mine was trammed to the top of the incline and hand sorted. Soft ore, which is the best grade, was washed off the base rock with a water jet at the top of the washing strips (picture below). These strips, akin to those used in alluvial gold and tin workings, were simply an inclined channel down which a constant flow of water was sent, followed by a series of sand collection boxes. Although the haematite is heavier than the other minerals present it is in the form of thin flakes which can be carried along in a flow of water. At the outflow end of each box was a ridge which held back the waste sand while the haematite flakes flowed on to the next box with the water and finally on to the settling tanks. Sand was throw back up onto the channel until no further haematite washed out. Coarse sand, which may contain useful ore, was sent down to the jigging box for further processing while the fine sand was waste.
Material from the mine containing a harder grade of ore was thrown across a 3/4" screen and what passed through was sent down a chute to the stamps to be crushed in order to liberate the haematite locked in the matrix. Larger blocks were broken up with a sledgehammer and together with medium sand from the washing strips was also sent to the stamps. The sand resulting from the stamping washed out into a spiral classifier which carried sandy material to the top of the spiral; any remaining ore was washed out in a second small set of strips. The good ore which washed straight out of the bottom of the classifier and was piped into settling tanks.
The jigging box or jigger (picture below) is a simple hand powered piece of equipment consisting of an outer box filled with water and a smaller inner box with a mesh bottom which contains the gravel to be washed. The inner box is suspended from a cantilevered arm and is jigged by dipped it vigourously in and out of the water. Haematite is heavier than the other minerals present and so gravel containing haematite settles to the bottom of the jigging box. From there it was sent to the stamps. Washings from the jigger went back to the strips to extract the any remaining haematite.
Once the concentrate in the tanks had settled out, it was
shovelled into trams and sent to the Drying Shed, where
it was laid to a spade depth on the heated drying floor.
The dried concentrate was raised by an elevator and
dropped into a rotating sieve, both driven by the
waterwheel. The finished product was packed into barrels,
weighed and carried out onto the loading bay to await removal usually to
Lustleigh Station.
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Washing strips in action
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| The jigger with the washing strips at top left and the mill in the background | 
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