Careful sorting and stacking of slate shingles at the Greaves' Wharf in Portmadog, #Wales #geology #thestoryofslate

Sequence of images capturing the 1896 'Great Blast' at the #Penrhyn Quarry, #Wales - they used 7 tons of gunpowder! #geology #thestoryofslate

Similar to other regions in the USA following large urban fires, slate 'migrated' along rivers & railways to New Orleans #geology #thestoryofslate

Sorting and splitting slate in a splitting shed of the #Honister Slate Quarry, #Cumbria. #geology #thestoryofslate

A well-worn grandfather clock carved from a single block of slate. Provenance unknown #geology #thestoryofslate

Detailed image of Penrhyn Quarry, North #Wales c1880s showing use of rails along benches and a few blast shelters. Very different from today's view! #geology #thestoryofslate

1912 map depicting the location of purple & green slates in the vicinity of Ransom Sound, #Newfoundland #geology #thestoryofslate

Quite the hat collection in this image of the Whitesell Slate Quarry in Belfast, #Pennsylvania c.1904 #geology #thestoryofslate

Historical slate quarries in #Swithland Leicestershire, UK - which was the source for many early Swithland gravestones, #geology #thestoryofslate

A fantasict visual summary of "Life In A Pennyslvania Slate Quarry" from Once A Week Magazine c.1890, depicting headframes, cableways, cable carriages, a signal shanty, trimming sheds, and slate banks. #geology #thestoryofslate

Although #Vermont is best known for the Slate Valley, there were other smaller deposits located around the state. This stereoview depicts a railroad serving the dark black unfading slate that was quarried in and around Northfield, #VT #geology #thestoryofslate

Hand-drawn map of the Cardigan Slate Works near Cwmerau, Cardiganshire in North #Wales depicting tramway locations #geology #thestoryofslate

Aerial view of Blaenau Ffestiniog, #Wales with extensive slate tips - most moved by hand! #geology #thestoryofslate

Hand-labeled sketch map of one of the slate belts cutting through North #Wales, Caernarfonshire c.1874 #geology #thestoryofslate

Impressive saw advertised for use in milling structural slate, - although OSHA might be concerned with the 'open concept' setup... #geology #thestoryofslate

Gwyn Arvon translates to white or blessed Arvon; but really it means a house made of slate! Clapboard siding, shingles, window sills, and even wainscoting! in #Arvonia, #Virginia. #geology #thestoryofslate

A simple but elegant beveling on a grave marker carved in slate from Monson, #Maine betraying the areas Scandinavian immigration. #geology #thestoryofslate

One of the larger quarries in $Monson, #Maine now drowned but its retaining wall is still impressive & sturdy! #geology #thestoryofslate

Impressive looking - albeit it small - former prison in Delta, #Pennsylvania made with Peach Bottom Slate & Cardiff Conglomerate #geology #thestoryofslate

A slate monument carved from #Monson slate still holding an exceptional edge after 100+ years exposed to the #Maine elements. #geology #thestoryofslate