Unique pithead colliery buildings near Blackwood, which were once at the epicentre of the South Wales colliery industry, could be converted to luxury apartments.

The two Grade II listed buildings and a parcel of development land make up part of the former Penallta Colliery, Hengoed.

The Power Hall is for auction with a guide price of £325,000+, the Bath House has a guide price of £125,000+ and the 3.7 acres of land to the rear of the Power Hall has a guide price of £225,000+.

Keri Harding-Jones, of Paul Fosh Auctions, which is selling the property, said: “The properties we have for sale represent unique examples of fragments of the industrial heritage of South Wales and its coal mining history.

"The three individual lots on offer for sale present a range of different opportunities for developers and we have already had quite a bit of interest in the properties and the land.

“The Power Hall, which was constructed in 1906 of pennant sandstone and red brick dressing, covers an area of some 4.2 acres. The building benefits from planning permission for conversion to 42, two-bedroom apartments and six, one-bedroom flats.

“Forming part of the pithead complex at Penallta Colliery, The Bath House was built in 1938 and is a rare example of the International Modernist style of architecture to be found in Wales. The building has planning permission for conversion to 33 apartments including six penthouses and five, three-bed, terraced houses.”

The Bath House building includes a semi-circular, single storey side wing, together with a central light well.

The 3.7 acres of development land to the rear of The Power Hall has planning permission for the construction of 36 properties.

The site is close to the Cwm Calon housing development, just outside Ystrad Mynach and close to Penallta Parc.

Penallta Colliery, which dates from 1905 when the first shaft was sunk by industry giant Powell Duffryn, employed some 3,200 men at its height in the 1930s and was one of the most productive mines in the world.

Penallta was at the vanguard of mining development and the colliery held the record in Europe in 1935 for the amount of coal wound (mined) in 24 hours.

In 1930 alone Penallta Colliery produced 975,603 tons of coal. The colliery, which was nationalised by the UK Labour Government in 1947 and subsequently owned by the National Coal Board, was closed in 1991 after 86 years of coal production.

The auction, when the colliery properties and land and some 50 other properties will be on offer, is on Thursday, October 29, at The Park Inn Hotel, Llanedeyrn, Cardiff, starting at 5pm. For more details visit www.paulfoshauctions.com.