Kimberlite century accidentally cut into the blue ground and found gem-quality diamonds in quantity. The economic importance of the time was such that, with a flood of diamonds being found, the miners undercut each other's prices and eventually decreased the diamonds' value down to cost in a short time. Kimberlite Kimberlite is an igneous rock, which sometimes contains diamonds. It is named after the town of Kimberley in South Africa, where the discovery of an diamond called the Star of South Africa in 1869 spawned a diamond rush and the digging of the open-pit mine called the Big Hole. Previously, the
Fishguard Volcanic Group recognised within the Strumble Head area. It is composed of acid tuffs. Fishguard Volcanic Group The Fishguard Volcanic Group is an Ordovician lithostratigraphic group (a sequence of rock strata) in west Wales. The name is derived from the town of Fishguard in Pembrokeshire. This assemblage of rocks has also been referred to as the Fishguard Volcanic Series or Fishguard Volcanic Complex. These rocks are believed to be the source of the 'bluestones' which form a part of the well-known prehistoric monument of Stonehenge in southern England. The rocks are intermittently exposed in a belt of country running east from Strumble