The country rock at the mine is metamorphosed killas and greenstone overlying the Carn Brea granite.

The mine's main produce was copper and later tin, arsenic and wolframite,[1] also small amounts of the ores of bismuth, cobalt and uranium.

[4] This first profitable period lasted for ten years during which time a total of £32,256 dividends were paid on the 128 shares that had cost their owners a mere £5 each.

To solve this problem a Wetherill's Magnetic Separator, which could process 10 tons of ore per day, was installed.

[10] East Pool mine still had a problem with water coming from Wheal Agar, which was losing money at the time and kept threatening to switch off its pumps, which it did in late 1895.

[2] In 1913 the mine converted from a company that was run on the cost-book principle to a limited company called East Pool and Agar Ltd.[12] Since the 1860s, the mine had had an extensive ore processing plant located just over a mile to the east in the Red River valley at Tolvaddon,[13] and from 1903 until August 1934 ore was transported there via a mineral tramway which used part of the track of the Camborne and Redruth Tramways, going through Pool village.

[14] After the tramway closed in 1934 the ore was carried by an aerial ropeway which ran directly across the countryside to the mill.

[12] In 1924 a notable 90-inch (2.3 m) pumping engine was installed at this shaft, having been moved from Carn Brea mine where it had lain unused since 1914.

The unique feature of this stack, the vertical letters "EPAL" displayed in white bricks near the top, is still visible.

As well as standing for "East Pool and Agar Limited", "EPAL" was also the brand name of the arsenic sold by the company.