19th century tin processing and a little nostalgia at Camborne's King Edward Mine Museum

I need very little excuse to visit the King Edward Mine (KEM) Museum in Camborne. It is only 12 miles from Falmouth, and is without doubt one of the world's finest mining museums, and an absolute must for anyone interested in early mining industry. There are very few, if any, places in the world where you can see 19th century gravity concentrators, such as round frames, buddles, Frue Vanners and rag frames, in operation.

Yesterday there was a very well attended Open Day and it was good to catch up with many of our sundowner regulars who are volunteers and give their free time to developing the site and to acting as knowledgeable guides.

KEM is the oldest complete mine site left in Cornwall. The mine was formerly part of South Condurrow Mine, which was abandoned in 1896. Re-opened and developed as a fully operational/training mine by the Camborne School of Mines (CSM), KEM was used up to the mid 1970s when the mill became a store. In 1987 a volunteer group was formed who restored the mill using rescued machinery.

The star attractions in the mill, which simulates operations much as they would have been in the early years of last century, are the Californian Stamps and the Rag Frames, and Carol Richards, a Director of Camborne School of Mines (CSM) Association and a long-term KEM volunteer, has produced two excellent videos showing the stamps and the rag frames in operation.

Carol Richards

Californian stamps were introduced in America during the gold rush of the late 1840s and differed from the traditional Cornish stamps in that the heads were circular in cross-section, rather than square, and the cams that lifted the stems were bevelled, so that as each head was lifted it turned slightly, thus reducing wear. A heavier, re-designed version of this stamp began to be used in Cornwall in the early 20th century.

The stamp battery at KEM is very small, but visitors are always impressed by the deafening noise, which gives some impression of what the now tranquil scene outside KEM must once have been like. The Museum is in the centre of the Camborne mining district, surrounded by ruined engine houses, some of which drove huge stamp batteries. With the engine houses spewing flame and black smoke from their chimneys, amidst a background of the continuous drum of the stamps, the nearby villages could not have beeen described as prime real estate, and it is pretty obvious that licence to operate was not a major consideration in those days.

Rag frames were simple but effective machines, their operation being shown clearly in Carol's video. Like round frames, they were used for the automatic treatment of fine cassiterite slimes, and were developed from hand-operated wooden frames, tended by girls, or bal maidens, which were in use for well over 100 years, until the 1860s.

Bal maidens by the rag frames at Wheal Grenville, adjacent to KEM, c1900

The automatic frame was developed in 1860 and thousands were installed by mines and tin streamers as the recovery of fine tin became important. Many hundreds of rag frames would be linked together to form a “slimes plant” and would have been a common surface feature on many 19th and early 20th century Cornish mines.

Rag frames at the Dolcoath mine, Camborne, in the 1890s

As rag frames were made entirely of wood, nothing remains of these ingenious devices, and the only place where they can now be seen in action is at KEM, and they have always generated much interest during MEI Conference visits to the mill.

Physical Separation '13 delegates by the rag frames

The KEM rag frames were built in the early 1990s by a KEM volunteer, Willie Uren (1925-2010), who had spent most of his working life in the mill at the South Crofty tin mine in Camborne. During his lifetime he saw the traditional equipment, such as stamps, vanners and buddles, replaced by heavy medium separation, ball mills, hydrosizers etc. He came to KEM in 1990 when work on the mill was just commencing and Cornwall was being scoured for old machinery, where it was repaired and erected under Willie's guidance.

My visits to KEM are also tinged with nostalgia as it was here that I spent my first few months at CSM from late 1974 until the move to the new premises between Camborne and Redruth in 1975. My first office at CSM was an old broom cupboard in the KEM Survey Office, and laboratory practical sessions were carried out on the disparate pieces of equipment which were in what is now the museum's mill, which was piercingly cold in winter. Not too far away, in the centre of Camborne, was the student union and squash courts, and it was great to see the old squash honours board yesterday, which has recently been found after all those years.

In my old office, and the recovered CSM squash club honours board

Thanks to everyone at CSM for a great day out yesterday.

Twitter @barrywills