Cockercombe Tuff is a greenish-grey, hard pyroclastic rock, formed by the compression of volcanic ash

Volcanic ash

Volcanic ash consists of small tephra, which are bits of pulverized rock and glass created by volcanic eruptions, less than in diameter. There are three mechanisms of volcanic ash formation: gas release under decompression causing magmatic eruptions; thermal contraction from chilling on contact...

 containing high quantities of chlorite

Chlorite

The chlorite ion is ClO2−. A chlorite is a compound that contains this group,with chlorine in oxidation state +3. Chlorites are also known as salts of chlorous acid.-Oxidation states:...

, which gives it its distinctive colour. It is found almost exclusively in the south-eastern end of the Quantock Hills

Quantock Hills

The Quantock Hills is a range of hills west of Bridgwater in Somerset, England. The Quantock Hills were England’s first Area of Outstanding Natural Beauty being designated in 1956 and consists of large amounts of heathland, oak woodlands, ancient parklands and agricultural land.The hills run from...

  near Cockercombe

Cockercombe

Cockercombe is a small village within the civil parish of West Bagborough in the West Somerset district of Somerset, England. Its nearest town is Taunton, which lies approximately away from the village....

, Somerset

Somerset

The ceremonial and non-metropolitan county of Somerset in South West England borders Bristol and Gloucestershire to the north, Wiltshire to the east, Dorset to the south-east, and Devon to the south-west. It is partly bounded to the north and west by the Bristol Channel and the estuary of the...

, England from where it has been quarried for centuries.

Quantock Lodge

Quantock Lodge

] Quantock Lodge is a green-grey nineteenth-century mansion built by Henry Clutton from Cockercombe tuff and is located near the hamlet of Aley, near the village of Over Stowey in the English county of Somerset. It was the family home of Henry Labouchere, 1st Baron Taunton, and in the 1960s was...

is built from Cockercombe tuff.