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The Wheal Ludcott Silver Deposit

Last Updated: 6th Oct 2009

By Steve Rust

The Wheal Ludcott Silver Deposite


The Wheal Ludcott mine is located about 4 kms E.N.E of the market town of Liskeard on the eastern side of Cornwall. The mine worked two approximately north-south lodes intersected by at least three east-west faults or slides.
Wheal Ludcott was opened in 1851, when a Mr Crouch obtained a lease for 21 years. Captain Dunstan was appointed as the mine manager, an adit was driven north on the western load. And then crosscut east to try and locate the Wheal Wray lode. The endeavour was not a success, and Captain Dunstan left the mine soon after. In 1852 the position was taken by a Captain Knapp, with John Taylor as the mine purser. The adit was cross-cut 20 Fathoms further north, but the Wray lode was found to be poor. All attention was now concentrated on the west lode, which was developed to a final depth of 60 fathoms. Later another trial was made on the east (Wrey) lode were a winz was sunk in the sole of the cross-cut adit to a depth of 8 fathoms. In the bottom of the winz silver-lead ore was found producing half a ton per fathom. To develop and confirm the deposit a shaft was sunk to a depth of 50 fathoms. This being drained by flatrods connected to a small rotary engine on the western shaft. Later the east lode was worked more effectively by the sinking of Willcocks shaft to an ultimate depth of 132 fathoms.

In 1860 the lode in the Wheal Wray mine to the north was showing signs of becoming poor, and the owners decided to give the mine up. This presented a major problem to the adventures in Weal Ludcott, as a number of levels interconnected the two mines. Negotiations were entered into between the two mine owners., Wheal Wray was purchased for £3438, paid for in three instalments. In late 1861 the mines became known as Wheal Wray and Ludcott United. After the mines were united the Wray shaft was depend to 116 fathoms, where shoots of galena were associated with an eleven dyke. The mines were said to have been a well run concern which enabled them to give dividends from a largely bunchy orebody. The mine appears to have been most productive from 1860-65, after this date there is not a lot written about the mines which may have closed in 1874. There was a proposed reworking of the mines in 1875 when the 80” beam engine was purchased from Wheal Mary Ann, but in was never moved to its new site

In 1862 an accident was recorded by The Cornish Times
(FATAL MINE ACCIDENT On Saturday last and accident happened at Wheal Ludcott Mine, St Ive. It appears a pair of men were engaged sinking a winze in the 38 fathom level. They had blasted a hole at the bottom of the winze, and Caleb Chapman went down to see what effect the hole had produced, and was being drawn up by his comrade, who was at the windlass. Before he reached the top of the winze, by some means he fell out of the rope, it is supposed about six fathoms. Assistance was immediately obtained; the fellow as not dead when his comrade came to him, but he died before he could be brought to the surface. An inquest was held on the body on Monday, by Mr Jagoe, coroner, when a verdict of ‘Accidental Death’ was returned. Chapman was 25 years of age, and leaves a wife and two children to mourn their loss.)



The two lodes are intersected and faulted by 3 east-west slides, a fourth my occur in the North Trelawny mine, as the adit of this mine was said to have been driven on the course of a slide. The intersection of the lodes and slides is complex, old writers record that not only did the slides dislocate the lodes, but that the lodes also had some influence on the slides.

The silver deposit was discovered in late 1861 when the 70 fathom level was being driven through the north slide in to Wheal Wrey, There was also said to have been some indications of silver in the 60 fathom level, and was finaly worked to the 84 fathom level. Other levels where also tried at lode-slide intersections although nothing is recorded as having been found. A small extension of the silver deposit was located some 8 fathoms east of the main orebody . Most of the silver was found in the two dislocated parts of the eastern load, which was thrown 3 fathoms. The sliver bearing part of the load was upto 3 feet thick against the footwall. Consisting of galena, argentite and native silver as the main ore with some pyragyrite, proustite, and stephanite, argentojarosite has also been recorded. Pyrite, sphalerite, quartz and siderite were also found in the deposit.
By 1864 the silver deposit was all but worked out, having produced 306 tons of silver ore, being the second highest recorded output from the West Country. This relatively small silver ore body has produced some of Britains best examples of silver sulphides and sulphosalts, although very few examples have survived ( probably less than 20 specimens).
In J.H.Collins records after Davis. That ½” inch cubo-octahedrons of argentite occur with stephanite crystals to 1 ½” inches long. Also argentite was recorded as excellent dendritic forms, with individual crystals to 3/8” showing skeletal habit, and as round complex crystals to 3/16”.
While the deposit was being worked a small number of native silver specimens found there way in to old collections. The examples seen consisted of specimens to 6” with masses of intertwining curled wires, and contorted thread-like forms to 1/8” which are very rich for Cornish silvers.
Proustite was found as small masses with tiny micro crystals.
Pyrargyrite occurred as crystals to 5mm in a fine grained galena-sphalerite-pyrargarite ore.

Many othere West County mines have records of silver minerals being found in them in very limited amounts.
Any specimens from them must be considered very rare.



Refs:

Collins, J.H. 1905 Notes on the Lead-bering Lodes of the West Of England. Trans.
Royal Geol. Soc . Cornwall Vol 12.

Collins, J.H. 1904 The Precious Metals in the West Of England. Journ. Royal. Inst.
Cornwall. Vol 16.

Collins, J.H. 1871 The Mineralogy of Cornwall & Devon ( Reprinted 1969)

Dines, H.G. 1956 The Metalliferous Mining Region of South-west England. Mem.
Geol. Surv. G.B. Vol 2.

Greg & Lettsom 1858 The Mineralogy of Great Britain & Ireland (Reprint 1977)

Henwood, W.J. 1871 Observations on Metalliferous Deposits Trans Royal. Geol.
Soc. Cornwall Vol 8.

Salmon, H.C. 1862 Illustrated Notes on Prominent Mines. Mining and Smelting
Magazine Vol 2.

Thomas Spargo. 1865 The Mines of Cornwall & Devon.

Rust.S 1983 Wheal Wrey & Ludcott United. Mineral Realm Vol 2 No 6.

Stephans, F.J. 1932 The Ancient Mining Districts of Cornwall. Rep. Royal.
Cornwall Poly. Soc. Vol 7.

Tindle, A.G. 2008 Minerals of Britain and Ireland.

Webb& Geach 1863 The History and Progress of Mining in the Caradon & Liskeard
District.




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