Search results
Results from the WOW.Com Content Network
Slate is a fine-grained, metamorphic rock that shows no obvious compositional layering but can easily be split into thin slabs and plates. [2] [3] It is usually formed by low-grade regional metamorphism of mudrock.
The world's biggest consumer of slate is France, followed by the UK, USA and Germany. In 2012, Spain produced more than 580,000 tonnes (570,000 long tons; 640,000 short tons) of slate worth about $380 million. This made it the largest slate producer in the world, followed by China and Brazil. [3]
Slate has been quarried in north Wales for almost two millennia with the Segontium Roman fort at Caernarfon being roofed by local slate in the late second century. Export of slate has been carried out for several centuries, which was recently confirmed by the discovery in the Menai Strait of the wreck of a 16th-century wooden ship carrying finished slates.
Since slate is formed in the lower realm of metamorphism, based on pressure and temperature, slate retains its stratification and can be defined as a hard, fine-grained rock. [3] Slate is often used for roofing, flooring, or old-fashioned stone walls. It has an attractive appearance, and its ideal cleavage and smooth texture are desirable.
Slate tiles are used in construction, particularly as roof shingle. [3] Quartzite is sufficiently hard and dense that it is difficult to quarry. However, some quartzite is used as dimension stone, often as slabs for flooring, walls, or stairsteps. About 6% of crushed stone, used mostly for road aggregate, is quartzite. [4]
The NFL did something different this year with its Christmas slate, partnering with Netflix to stream a pair of unusually timed Wednesday games. They announced the results a day later. Netflix ...
3. Costco's valuation. Shares of Costco have absolutely trounced the broader S&P 500 in the past decade. Part of the reason for this outperformance is consistently solid financial results, with ...
The pumping house at Dorothea Moel Tryfan and Alexandra quarries. The Slate Industry in the Nantlle Valley was the major industry of the area. The Nantlle Valley is the site of oldest slate quarry in Wales at Cilgwyn, and during the nineteenth and twentieth centuries it was a major centre of the Slate industry in Wales.