Weren't we lucky 300 million years ago?

August is a funny old month in Cornwall, its often the best weather but the influx of holidaymakers does present challenges all round.  However, tourism makes up about 20% of Cornwall’s $9 billion economy so no-one can deny it’s vital.

But it wasn’t always like that.  Cornwall has always been resilient and in the past, the main economic activity was smuggling and shipwrecks (least said…), china clay, mining (mainly copper and tin) and pilchards – as fishy as that may seem.  Around 1700, the salted pilchard industry had the same value as the mining industry, and few counties can claim that.

Trudging up towards Brown Willy, I was struck by the complete absence of pilchards and how lucky we are that we have the Cornish granite to bolster our economy.  As we noted in an earlier blog, our granites that form the prominent Cornish uplands were intruded into the area 300 million years ago.

Like everything in life, there’s a bigger picture.  Our Earth, if you cut it in half, is a bit like an egg.  The crust is like the shell, solid and quite thin.  The mantle, like the white, is a molten rock and the core, or the yolk, is made of iron and nickel and is estimated to be 5500°C, similar to a Saturday afternoon barbie when the burgers land on it.  Anyway, the point is that, like a broken boiled egg, the earth’s crust is made up of a series of plates which float on the mantle and are moved around by the heat of the mantle.

All this is the reason for the way the Earth looks today.  As plates collide, one dives under the other and creates double thickness of crust which creates a mountain range – like the Andes and Himalayas. Other plates create new crust through volcanic activity, so the plates move further apart. It’s amazing to think that for anyone 50 years old, in that life span, New York and London have physically moved 6 feet further apart, which might explain increased air fares.  It’s also the reason we have a series of islands in the mid-Atlantic such as St Helena, Ascension Island and Tristan da Cunha.

Anyway, 300 million years ago the area we now call Britain was part of a larger super-continent called Laurasia and the other super-continent, Gondwanaland, collided with it to eventually create one huge land mass called Pangea (meaning in Greek “whole land”, geologists are very clever).  Cornwall and Devon were affected by this period and the result was the Cornish granites were formed.

With this episode, not only did we get the granites but several precious metals as well.  The net result is that this chance occurrence – which didn’t happen in the rest of Britain – we got such metals in economic concentrations, the granite itself and, after millions of years of weathering, the china clay that still forms an important part of the Cornish economy.

It’s incredible to think that this one episode in our dim and distant past created so many benefits we see today and in our recent past.  The age of steam, bringing enormous power hitherto impossible, allowed rock to be hauled, crushed and water to be pumped to create a new industry. Even now, new mineral sources such as lithium are being assessed to potentially breathe new life into the industry.

View from Alex Tor with granite

But, it’s not only the mineral wealth the granite has bestowed on us.  It creates the uplands and the scenery we know so well and that has shaped the history of Cornwall.  Our tors are formed because of the way the granite formed and has been eroded, they create the source for the famous rivers and our recreational environment.

But what’s in a name?  The name Bodmin Moor was recorded in November 1812 in the Royal Cornwall Gazette but it was initially called Fowey Moor, being the source of the River Fowey

Although the original Neolithic people, living there 4000 years ago probably just called it home.

This photo, with a fairly unusual sign for the moor, is in Camelford.  The War Memorial is located on Roughtor, one of two memorials, the other commemorates the murder of Charlotte Dymond in 1844.  Charlotte was only 18 when she was found dead and a local labourer was found guilty of the crime and executed at Bodmin jail.  Her ghost is rumoured to frequent the moor dressed in the Sunday best clothing she was wearing at the time.

Standing at the base of Roughtor on a cool windy day, it didn’t feel like summer but I did see a Wheatear still braving the elements before heading to Africa.  Wheatears are found in Siberia and Greenland in summer and make one of the longest migrations known for their winter holidays.