Saturday 29 April 2017

Mandale Limestone


A sample of Mandale limestone

During my 9 month long exploration of the mediaeval churches in and around South Yorkshire, finishing at the church of St. Nicholas in High Bradfield, I had achieved my principal objective of refining and further developing my geological skills that I consider to be of practical value to archaeologists and architects.

A general view of Clifton Park Museum

As every geologist whose house and garden is full of rocks, fossils and minerals will know, I encountered various places where I felt compelled to collect a piece of rock – from a natural outcrop or a dry stone wall and very occasionally from an historic building – without recourse to using a geological hammer.

A geological survey without resort to the use of a geological hammer

20 years ago, while living in Bakewell and undertaking a survey of the RIGS within the Peak District National Park, I made an effort to find the Once-a-week quarry in Sheldon and to acquire a sample of polished Mandale limestone - which I added to my very large collection of building stones that later formed the basis of the Triton Stone Library in London.

The Triton Stone Library

Having explored very many of the dales that are deeply cut into the Carboniferous limestone within this region, I had seen a wide variety of corals, crinoids and brachiopods exposed in their weathered rock faces – as well as in countless dry stone walls and vernacular buildings; however, when polished, this particular stone becomes even more spectacular.

A  sample of Mandale limestone used as a stepping stone

My sample of Mandale limestone was never included in the Triton Stone Library and now forms one of two stepping stones that can be found in my herb garden and, although its polished surface has long since weathered away and algae have penetrated any open pores, it is has stood the test of time extremely well compared to a similar sized sample of Ancaster limestone - of the same age - that has just crumbled away.

Mandale limestone and Ancaster limestone

When working for Clifton Park Museum in Rotherham, where Mandale limestone is used for some of the floors and fireplaces in this 18th century building, I noticed that its floors were severely deteriorating and, on more than one occasion, I was asked by the person responsible for its maintenance to advise on the best method of repair – as the previous attempts with epoxy resin had clearly failed.

A defect in the Mandale limestone in the floor of Clifton Park Museum

Whilst taking another look at the floor, while visiting the Rotherham Show, I saw that a sample of Mandale limestone had actually been displayed in the museum several years ago and so I decided to arrange a visit to Rowsley, where Natural Stones Sales Ltd. are now marketing this stone.

An example of Mandale limestone in Rotherham

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