Puddingstone (rock)

Puddingstone, also known as either Pudding stone or Plum-pudding stone, is a popular name applied to a conglomerate that consists of distinctly rounded pebbles whose colors contrast sharply with the color of the finer-grained, often sandy, matrix or cement surrounding them. The rounded pebbles and the sharp constrast in color gives this type of conglomerate the appearance of a raisin or Christmas pudding.^[1][2]

There are different types of puddingstone, with different makeup and geographical distribution. These include:

• Hertfordshire puddingstone, principally found in Hertfordshire, England
• Bearfort Mountain. Boonton, Rockaway Township puddingstone, is a purple puddingstone found in northern New Jersey. Geologically, it is formed of Paleozoic sandstone and quartz conglomerate. The puddingstone Schunemunk conglomerate is studded with pebbles of pink sandstone and white quartz.
• Roxbury puddingstone, principally found in and around Boston, Massachusetts
• Plumstead Common has a fine example of puddingstone, probably left behind after the last Ice Age
• St. Joseph Island puddingstone, found in the St. Mary's River area of Northern Ontario contains red and brown pieces of jasper, a kind of quartz.

References

1. ^ Neuendorf, K.E.K., J.P. Mehl, Jr., and J.A. Jackson (2005) Glossary of Geology. Springer-Verlag, New York, 779 pp., ISBN 3-540-27951-2
2. ^ The McGraw-Hill Companies (2003) McGraw-Hill dictionary of geology and mineralogy, 2nd ed. The McGraw-Hill Companies, Inc, New York, 420 pp., ISBN 0-07-141044-9