Accretionary lapilli tuff is an igneous pyroclastic rock, these samples come from Longsleddle, Cumbria in the UK and forms when hot ash and debris is ejected from as volcano. Some of this material is held together by moisture and once heavy enough, falls into the ash below forming small ‘spots’ within the material, creating a speckled rock. The samples are suitable both for young and serious collectors as well as educational use and are supplied in various sizes with a card tray and label.
Andesite igneous rock specimens of late Ordovician age which form part of the Barrowdale volcanic group. The rocks come from Cumbria, UK and have a dark colouration with a blue tint and may contain augite crystals. The rocks are intermediate in chemistry and suitable for higher level education to explain the difference in various igneous groups. Samples are available in 3 sizes and will come supplied in a card tray with an information label.
Augite andesite igneous rock specimens from Thirlmere, Cumbria, UK which are of late Ordovician age which form part of the Barrowdale volcanic group. The samples are of intermediate composition and contain phenocrysts of the pyroxene mineral, augite, giving the normally dark blue rock a black speckled appearance. The samples are available in 3 sizes and come supplied in a card tray with a label.
Augite granophyre igneous rock specimens from Carrockfell, Keswick in Cumbria, UK. Excellent pieces exhibiting a medium grain size of crystals which constitute this rock including, augite, quartz and feldspars and shows a granophyric texture. Suitable for avid collectors and higher educational use, the samples come supplied in a sized card tray with an information label.
Banded tuff rock specimens from Cumbria, UK. An extrusive igneous rock with a felsic chemistry and rhyolitic texture, the specimen exhibit a pink colouration due to the presence of feldspar as well as banded formations. Available in various sizes and supplied in a card tray with a label.
Diorite rock specimens from Cockermouth, Cumbria, is an intrusive igneous rock from the Ordovician period with a coarse, phaneratic texture composed of plagioclase feldspar, biotite mica as well as hornblende with intermediate chemistry. Found with the Skiddaw group, the rock samples are more suited for serious collectors and higher level education to describe the chemistry and mineralogy of various igneous groups. Available in 3 sizes and supplied in a card tray with an information label.
Ignimbirte welded tuff is a pyroclastic rock of any origin formed through volcanic processes, the rock appears to show streaks of welded material on some surfaces and appears to be rhyolitic on the inside. Specimens come from Cumbria and are available in various sizes.