The Stonemason at Culzean

by Andrew Bradley

Andrew Bradley has been a stonemason for  25 years , and has been based at Culzean since 1981. During the last three years Andrew has headed up a new stonemasonry unit that works effectively as an independent firm, pricing at competitive rates for work to be done at Culzean, other NTS and sites that require restoration or other high quality stone work to be undertaken.

Andrew was a pains to point out this aspect of the Trust's work. The NTS not only seeks to ensure the long term future of many historic sites but also seeks to preserve the skills and craftsmanship necessary to do it. The training is currently in the form of 4 year apprenticeships, sponsored by the Trust.

Andrew's unit has undertaken work on all parts of Culzean including the beautiful fountain in the formal garden, the viaduct, the walls of many buildings, chimneys, etc.

Andrew described an important job they had undertaken for the David Livingstone National Memorial, at Blantyre. The work involved the reconstruction of a large stone sphere representing the world with very complex wedge shaped curved blocks cut to amazing accuracy for an exact fit. A special hydraulic lime mortar was used as the jointing compound. The mortar has to be slightly softer than the rock and just keeps the blocks apart.

On the left is a sample of the blocks used to create the sphere.

Andrew described some of the difficulties involved in cutting blocks of this style and coping with different types of stone.

He showed us some of the stonemason's tools. There has been little fundamental change to these tools over the centuries and although modern chisels have tungsten inserts and mallets have plastic heads, the tool shape and use has remained the same.  There is a bill from the 1780's In the Culzean archives from a local blacksmith for sharpening 3700 mason's chisels in one month. This was due to working the sandstone which blunts chisels very quickly (after all, you can use sandstone to sharpen chisels!). The blacksmith's role in sharpening chisels was very important as each chisel was tempered depending on the nature of the stone being worked. Marble would require a softer tempering while sandstone had to be very hard. The Crusaders brought back the skills of using mallet and chisel from the Arabs. Before that, stone masons used axes so could only shallow relief in their carving (Romanesque). The change to chisel and mallet brought with it the Gothic stonework.  Individual stones can be dated using mason's tool marks, but whole buildings usually have many other factors allowing more accurate dating.

Nowadays most stonemasons work to a contracted price, but when Culzean was developed in the late 1700s they were paid by each block cut. As a result, each stonemason put his mark on his work so it could be identified and he could be paid his dues. To tamper with another mason's mark was a very serious offence!

The stonemason's work at Culzean (as at many other historical sites) has changed in recent years. Some time back, restoration meant rebuilding to returning a site to it's original condition (or that of a certain date). The more recent view is that work should be undertaken to preserve and ensure the long term survival of the sites and no more than that. So where heavily weather blocks of stone would have been replaced with newly carved ones to return it to it's original look, it would now only be replaced if it was unsafe. No attempt is made to repair sites with 'aged' work. As Andrew put it "stones with corners knocked off don't look old, they look like new stones with the corners knocked off!".

There are stones on the beach at Culzean worked by stonemasons over 200 to 300 years ago. There were some 400 stone quarries in the Culzean area in the 18th century. All the stone used at Culzean was quarried within 3 or 4 miles and was selected to be easy to work. Now there are about 9. Care is taken during restoration to use stone that matches the original as much as possible. Old stone is not salvaged: For a start you don't want to encourage the demolition of one ancient site with the excuse of restoring another. Also, stone case hardens with age; when it is first quarried the stone has a softer more even texture and can be worked more easily as a result of the moisture in the stone. As this dries out the stone case hardens (produces a hard skin) which protects the stone from weathering. One danger of over cleaning stone buildings is that if the case hardening is removed the stone will deteriorate quicker.

Many other topics were covered by Andrew in his talk which was thoroughly enjoyed by all. We wish him many thanks for coming to the meeting and all success for the future.

John Rattenbury.