BGS Rock Classification Scheme
Hornfels - A type of contact metamorphic rock. Hornfels is a variant of granofels. The term is applied to a hard fine- to medium-grained rock of unknown protolith and modal composition which lacks parting planes and has recrystallised as a result of contact metamorphism. British Geological Survey Research Report RR/99/02, section 6.1.
| Code | HNFELS |
|---|---|
| Description | Hornfels - A type of contact metamorphic rock. Hornfels is a variant of granofels. The term is applied to a hard fine- to medium-grained rock of unknown protolith and modal composition which lacks parting planes and has recrystallised as a result of contact metamorphism. British Geological Survey Research Report RR/99/02, section 6.1. |
| Qualifiers | No qualifiers currently exist. |
| Definition | Hard, fine to medium-grained (av. 0.032-2mm) granoblastic rock (protolith undefined), recrystallised by contact metamorphism, lacks parting planes, pre-existing features identified by lithological heterogeneities; a granofels |
| Linked data | http://data.bgs.ac.uk/id/EarthMaterialClass/RockName/HNFELS |
CAVEAT
"Thumbnail" definitions attached to some of the table entries are an interim attempt to provide simple short descriptions of the "unqualified" rock types presented within the BGS Rock Classification Scheme. Every effort has been made to ensure accuracy and consistency but minor contradictions or omissions might be present. The BGS welcomes any feedback pointing out such minor imperfections and/or providing constructive comment and suggestions for improvement of the definitions. In the first instance such feedback should be directed to Dr Tim McCormick.