Mui Wo Silver Mine Processing Plant

Tymon Mellor: A silver mine was operating in the hills behind Mui Wo between 1886 and 1896, developed and owned by Mr Ho A Mei, a local Hong Kong entrepreneur and social activist. Associated with the mine was a mineral processing plant, where the ore was crushed and smelted into lead and silver. The location of the plant has never been identified. There has been speculation over its location, including proposals in previous articles on this web site, but there has never been any conclusive proof revealed until now. The United Kingdom Hydrographic Office has an unpublished map from 1905 showing the location of the chimney associated with the processing plant chimney. This article identifies the location of the chimney and the associated processing plant.

Mui Wo Mine

The history of the silver mine at Mui Wo can be found in an earlier article on this web site, (see Related Indhhk articles below), but in summary, the mine was founded in March 1886 and operated until its closure in 1896. Galena, the mineral of lead and silver was extracted from the mine, and then transported using a 900m long aerial ropeway to a processing plant on the coast. A wooden pier provided marine access where mineral ore from a sister mine in the Mainland was brought ashore for smelting together with the Mui Wo Galena.

Processing Facility

The processing facility was ‘state of the art’, erected and operated by experienced personnel from the Cornish lead mines using the latest in British processing technology. The plant included rock crushers, smelting furnaces, and a materials laboratory, all powered by steam engines. The facility was housed in a steel structure 73m long, clad in galvanised iron sheeting. The Galena ore was crushed to a fine material with the heavier minerals separated out, to be taken to a furnace and heated to 1,450°C to 2,000°C, melting the ore and burning off the sulphur. During this process, the Galena would produce poisonous fumes, particularly sulphur dioxide and also vaporised lead. The fumes were removed via a large flue (a horizontal chimney) to a chimney built on the hillsides some 30m above the processing plant. In other facilities, boys were periodically sent into the flues to scrape condensed lead off the walls to return it for processing.

A contemporary account from 1905 described the facility and the chimney, “In the furnace house were eight furnaces of various type, all connected by flues and a condenser to a chimney, sixty feet high (18m), standing on the hillside about a hundred feet (30m) above their level”.  The chimney was very prominent and was a navigational land mark for many years. The article continues “the ruins of [the processing plant] which can be seen to day by those who go over to Lantao and anchor in Silver Mine Bay…the cemented floor is observed near the beach where it serves the peasants, from the dwellings close by, as a drying ground for rice and fish.”. It further notes, “On the neighbouring hillside stands the chimney, commanding an excellent view of the entrance to the mine, with tons of excavated earth banked up from the running stream some fifty feet below”.

I have been unable to find any further details of the processing plant, but the skill and knowledge of Cornish miners was recognised within the mining industry, and also that they travelled and established mining operations in other regions beyond their native Cornwall. One such mine, the Sikehead mine in the North Pennines in England, was established at around the same time as the Mui Wo facility using Cornish expertise. The flue and chimney of the Sikehead mine are well preserved.

Part of the flue, connecting the processing facility to the chimney is particularly well preserved, measuring approximately 1.7m wide by 1.7m high internally, with an oval cross- section and a paved floor. The chimney is approximately 15m tall with a 7m diameter stepped base with a flue opening 2m wide by 2.4m high. The chimney at Mui Wo is likely to be of a similar design.

Unpublished Map

In early August 2018 while researching the history of map making in Hong Kong, I was introduced to the archivists at the United Kingdom Hydrographic Office. Up to that moment, I was not aware that there was an archive in the Hydrographic Office or that they have an extensive collection of historic Hong Kong maps. During our correspondence, I discovered that they have a 1905 survey of Lantau Island and following an enquiry, they confirmed that it indicated a chimney in the Mui Wo area. I requested a copy of the map, to finally locate the chimney and fix the location of the processing facility; but there was a snag. The survey work was unpublished and permission was required from the authors, the British Military, to release the map. This was soon granted.

The unpublished survey was undertaken by HMS Rambler, an Algerine-class gun vessel launched in 1880, and which gave its name to the ‘Rambler Channel’, the stretch of water between Tsing Yi Island and Tsuen Wan and Kwai Chung. From 1886 and until decommissioning and being sold for scrap in 1907, she mostly served the ‘China Station’, operating in the southern China seas, and was permanently based in Hong Kong from February, 1889. She had a crew of 100 men, and was powered by a two-cylinder horizontal compound-expansion steam engine powering a single screw, giving a vessel speed of about 10.5 knots (19.4 km/h). The ship was involved in a number of surveys, including the 1888 survey of Hong Kong Harbour,  and later updates  and Hong Kong Waters East.

In early 1905, HMS Rambler, under the command of C E Monro, undertook a survey of southern Lantau. The chart focused on the seabed environment with the topography being sketched in from shore station and area partially walked over. In the area of Mui Wo, a chimney is indicated on the hillside at around the 100ft contour, with a clear view of the sea and mine operation.

Given the importance of the chimney as an identifiable feature for marine navigation, the chimney location would have been carefully surveyed. Overlaying the 1905 map with the other mine features, it is clear that the location is at the 900m distance identified for the aerial ropeway.

Location to Today

There is little surviving evidence to locate the chimney or the processing plant, and a review of aerial photographs from 1924 and 1963 provides no clear sign of any major structures.

The 1924 image does seem to indicate two small buildings to the west, and also a possible jetty location. The two buildings do not appear on the corresponding image from 1963, suggesting that they were not houses but something less tangible such as abandoned industrial buildings. The two aerial photos do however confirm that the site had not been under cultivation and that it would have been a suitable location for the facility. The 1963 aerial photo does indicate a network of footpaths on the hillside in the locale of the chimney along with the first signs of residential development, but there is nothing to indicate the presence of a chimney and industrial buildings.

A review of detailed mapping of the area also provides no evidence. However, that may be more a result of the lack of detail on the mapping. The Hong Kong Government has recently undertaken a LiDAR  survey of the area, using laser to create a 3D representation of change in slope. This survey suggests that there is a flat area on the hillside along with other features that may be related to the flue close to the location identified on the 1905 map.

Accessing the site is now very difficult due to the overgrown nature of the hillside. There are no obvious signs of the stone work and steel structures associated with the facility, as no doubt the materials were probably salvaged for other applications between 1910 and 1920. Only an archaeological exploration of the site may confirm the location of the facilities.

The Mui Wo silver mine formed part of the larger industrialisation of China at the end of the nineteenth century. In combination with the development of steam powered railways, modern mining technology combined with Chinese finance was seen as a way to open the nation to the world. However, the Boxer Uprising and the establishment of the Republic of China shortly afterwards, put an end to this brief moment of rapprochement.

Sources

• United Kingdom Hydrographic Office Archive https://www.gov.uk/guidance/the-ukho-archive
• China Sea Hongkong Approaches Lantau Island East Coast Surveyed by C E Monro RN (1905) Reproduced by permission of the Controller of Her Majesty’s Stationery Office and the UK Hydrographic Office
• Processing Ore – The Smelt Mill https://www.mylearning.org/stories/lead-mining-in-the-yorkshire-dales/69
• The Hongkong Telegraph, 30^th September, 1905
• Lead mining at Ramshaw https://historicengland.org.uk/listing/the-list/list-entry/1015862
• Sikehead lead smelting flue chimney and flue, http://www.geograph.org.uk/photo/2864208

• HMS Rambler https://en.wikipedia.org/wiki/HMS_Rambler_(1880)
• https://www.britishempire.co.uk/forces/navyships/gunboats/hmsrambler.htm
• National Collection of Aerial Photography, https://ncap.org.uk/frame/20-1-2-33-33

This article was first posted on 13th September 2018.

Related Indhhk articles:

1. The Silver Mine of Silver Mine Bay
2. Robey & Company, Lincoln, UK – suppliers of structure and machinery at Silver Mine, Mui Wo
3. Mui Wo Silver Mine – 1905 newspaper article
4. Mui Wo Silver Mine – Part One – The Owner
5. Mui Wo Silver Mine – Part Two The Mine