This very useful stone is found in the coal measures near Lydney and Coleford in Gloucestershire.

There are three distinct series or beds of considerable thickness. Of these the upper series consists of a soft, easily worked stone of various degrees of hardness. The second series in harder than the first, and the third harder than the second, and of a finer grit. Both the second and third series can be quarried in blocks of any size.

1 Mr. Trickett in Building Neits, 25th June 1871.

2 Mr. Trickett in Builders' Weekly Reporter, 23d June 1875.

3 Wray.

The first and second series are of a grey colour, the third is blue. Some i»f the stone has a brownish tint.

The stone weathers well if placed upon its natural bed. Some used in the churches of Newland, Staunton, and Mitcheldean, that has been exposed 400 years, still retains the tool-marks as sharp as ever, but this of course was from the best quarries, carefully selected.

There are a great many quarries in the hands of different proprietors. It is unnecessary to give their names.

The stone is admirably adapted for building, or for heavy engineering work such as bridges and docks.

Where Used

It has been used in the construction of Cardiff, Newport, Gloucester, and Swansea docks; Folly Bridge, Oxford; Cardiff Castle and National Provincial Bank, Marlborough; Cardiff new Barracks; port of Llan-daff; interior of St. John's and Exeter Colleges; Taylor and Randolph's buildings, Oxford; Eastun Castle and Witley Court, Doncaster, etc. etc.

Mansfield Stone is one of the best known and most important building stones in the country.

It is a siliceous dolomite (see p. 59), and is found near Mansfield, Nottinghamshire, in the Permian system, between the new red sandstone and the carboniferous series.

There are several beds found in the quarries, which differ considerably from one another both in composition and texture.

There are, however, two principal varieties of the stone sent into the market, the white and the red, both of them good for building purposes.

Of these varieties the red is considered more durable than the white. Both kinds last well in a clear atmosphere. They are all admirably adapted for the finest ashlar work, turned columns, mouldings, carvings, etc.