Detrital Andalusite in Tertiary and Post-tertiary sands

Abstract

Until quite recently, in spite of its characteristic features, andalusite had not been met with in the younger detrital rocks of Britain ; a few years ago, however, I remarked on its relative abundance in the older Pliocene sands of St. Erth and St. Agnes in the west of Cornwall. Its presence in these deposits, in which it is associated with pink garnet and cyanite, is easily explained by the close proximity of the areas of deposition to the metamorphic aureoles of the west of England granitemasses, in which andalusite of identical character is exceedingly common. It also occurs in fair quantity in the Pliocene sands of Lenham in Kent accompanied by cyanite, and together with cyanite and garnet in the Red and Norwich Crags and the Chillesford Beds in the east of England.