Rough-out of cannel coal or shale with perforation largely complete, used in the making of a bangle, from St Blane's

Trial design on a fragment of thin shale, rudely incised, from St Blane's, Bute

Flat, rectangular-section ring of shale, from a cairn at Limefield Farm, Wiston, South Lanarkshire, Bronze Age

One of a group of copper ores and other specimens illustrating the extraction of the metal - a sample of hard black shale from Morenci formation, Devonian Age

One of a group of copper ores and other specimens illustrating the extraction of the metal - a sample of ordinary shale from Morenci formation, Devonian Age

Sample of raw shale from Westwood Works, West Lothian

Tobacco pipe of carved shale: North America, Canada, Northwest Coast

Argillite tobacco pipe of with exterior of bowl carved in form of an eagle's or raven's head, the stem in form of three cloaked women in a canoe, the central figure wearing a lip stud, the one at the stern caught in the tentacles of a giant octopus, probably illustrating a well-known story: North America, Canada, Northwest Coast, Haida, early 19th century

Figure of the sun god Surya attended by Pingala and Dandin, with Usa and Pratyosa below dispelling darkness with their arrows, carved black shale: South Asia, India, Pala period, 11th century

Head carved in shale of a tirthankara, one of the twenty four teachers of the Jain religion: Asia, South Asia, Central India, 12th century

Fragment of a shale armlet of almost circular section with worn, broken edges, part of a finds assemblage from excavations at Dunadd, Kilmichael Glassary, Argyll, Scotland

Decorated slab slate/motif piece from excavations at Dunadd, Kilmichael Glassary, Argyll

Shale whorl or bead from excavations at Dunadd, Kilmichael Glassary, Argyll