 | | Ploughed field on west side of summit, Largy Hill, Lack, Co.Tyrone. |
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| Site Type: | Field | | Site Status: | local interest | | Council area: | Fermanagh & Omagh District Council | | Grid Reference: | H271655 | | Bing maps: | 54.53758,-7.58131 | | Google maps: | 54.53758,-7.58131 | | Rocks |
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| Rock Age: | Precambrian (Dalradian) | | Rock Type: | Schist | | Interest |
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| Minerals: | Almandine, Muscovite |
| Summary of site: |
| At this locality large, well-formed crystals of almandine garnet are found in a silvery schist within the Mullaghcarn Formation. These are ancient Dalradian rocks around 600 million years old but the crystals formed when they were metamorphosed during a continental collision with an island arc around 465 million years ago. Outcrop is poor and most crystals are found in rock fragments unearthed by ploughing. |
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