Basic Facts

The Rhynie Chert


  • The Rhynie chert is a rock containing exceptionally well-preserved fossil plants and animals (arthropods).

  • It is found near the village of Rhynie, Aberdeenshire, Scotland [map].

  • Discovered in 1912 by Dr William Mackie [History].

  • Chert is a hard silica-rich rock.

  • The age of the chert is Early Devonian (Pragian): between 400 and 412 Million years old [timescale].

  • At this time Scotland was situated around 28o south of the equator as part of a huge continent made up of northern Europe, North America and Greenland, called Laurussia [palaeogeographic map].

  • The cherts are altered siliceous sinters deposited by hot springs and geysers similar to those active today in Yellowstone National Park, USA.

  • The sinters coated and fossilised plants and animals preserving them in amazing detail.

  • The plant and animal fossils are important because they were some of the earliest colonisers of the land.

  • The fossils help us reconstruct early land-based ecosystems.

  • The oldest 'insect' fossils known, Rhyniella (a type of springtail) and Rhyniognatha (a primitive pterygote insect), have been found in the Rhynie chert.

  • The flora includes seven named higher land plants, all less than 40 cm tall. [plants].

  • At least fifteen different (valid) named species of early terrestrial and freshwater arthropods have been described from the chert, and still more are currently being described or await publication [animals].

  • Algae, fungi, a lichen and various bacteria are also fossilised in the chert.

  • The hot spring waters that deposited the sinter contained gold, arsenic, antimony and other metals.

  • The Rhynie chert is the oldest hot spring system known anywhere in the world where surface features such as geyser vents are preserved.