Flint is a mixture of crystalline silica (quartz) and hydrated silica (opal). Flints can vary in shape, size and colour. Three main types are used in construction: quarried (or virgin) flints, field flints and cobbles, which have been rounded by the action of water. The exact origins of flint, though much debated, are still unclear. The most generally accepted view is that it derives from the remains of minute silica-based sea organisms that used to live in the ancient shallow seas.

Geology and history

In the UK, flint can be found in many places across Southern England, principally along the course of a large horseshoe running between Lincolnshire and Oxfordshire and taking in the counties of Norfolk Suffolk, Essex, Kent, Sussex, Hampshire, Wiltshire, Berkshire and Buckinghamshire on the way. There are also isolated pockets in Dorset, Surrey and Hertfordshire. Found as pebbles and nodules in the Middle and Upper Chalk layers this beautiful stone has always been used in construction.

Treatment and uses in construction

Flint has been employed for many different purposes throughout history: as a functional material for defence and protection (castles and fortifications), in agricultural settings (to retain livestock) and for purely aesthetic and decorative purposes (ecclesiastical and domestic).

Flint is known as the ‘versatile stone’ because of the many styles and finishes to which it lends itself. It varies in shape, colour and form according to the part of the country it comes from. Experts can analyse pictures of a flint building and mortaring style and predict its age, where it was built and why.

With new builds, this is sadly becoming more difficult to do as materials are increasingly brought in from other regions and construction practice is frequently poor. We are dedicated to combatting both these practices.

Types of construction

The Flintman Company only lays flint freehand. We believe this is by far the preferred practice for achieving high quality results. Alternative methods within the flint construction industry include shuttering (laying blind behind fixed boards) and the use of flint blocks (pre-cast concrete blocks with flints set within the block). Shuttering has been around longer than flint blocking and is often reverted to when builders lack experience and knowledge of the materials. We believe this method can produce aesthetically inferior results.

But more recently flint blocks have had a far more damaging impact on the craft of flint. While it is true that there is a lack of skilled flint masons regionally and nationally, and that building regulations in the modern construction environment impose additional pressures, the practice of using flint blocks should not be encouraged.  As well as bringing alien materials in from a different geology, the choice of style and final finish is often poor whatever the quality of work on site. Now we are being forced to contend with blocks made of ‘dyed reconstituted stone’, which imitate real flint. It is a myth that these modern methods reduce costs. Even worse: their use contributes to, rather than addresses, the issue of declining skills that so threatens the health of the flint industry.