East Wheal Margaret is given in Kellys as working in 1856.
Wheal Margaret produced tin from 1790, 1798, 1840, 1855–77
1856 Kellys. Wheal Margaret Tin Mine is in the parish of Uny Lelant, C[or]nwall. The company is on the costbook system, and [consists o]f 112 [s]har[es. In 18]55 the dividends were £1,904, or £17 per share. The purser is W. S. Arthur, of Penzance.
1861 Thomas Uren, manager Wheal Margaret
1861 William Jenkin, engineer Wheal Margaret
1873 Kellys Directory Wheal Margaret 1873 tin mine in the parish of Uny Lelant, is held under lease for 21 years, granted by the HEARLE family, Messrs. WILLIAMS and the executors of W. B. TYRINGHAM esq., at a royalty of 1-18th. The country is granite. The known loads on the sett are four, running east and west. The known cross-courses two, running north and south. The dip is 18 inches in the fathom. The mine is worked and drained by two steam engines of 24-inch and 36-inch cylinder. Depth of engine shaft 200 fathoms. The company is on the costbook system, and consists of 896 shares. Purser Thomas TREWEEKE of St. Ives. Agent James MITCHELL
St Ives, Zennor and St Erth Mines