bellstones

What exactly is a bellstone??, someone told me many years ago, that they are drops of molten rock chucked out during a volcanic eruption that cooled quickly, and being very heavy and dense, gravity pulls them down through the earth.
I've had a look on google but can't find any reference to them.

Mikej In Marine and no doubt throughout the coal field as the coal face advance often you would encounter stone formations in the roof roughly the shape of a bell and was very heavy ironstone probably, these were very dangerous as often there were no visible signs in the roof so you could well timber up and not "catch " them so they would drop out between your supports with dire consequences, they were referred to as Bells in Marine but in Waunlwyd they took a different form more elongated and were referred to as "Pans". the last time I encountered a pan was on night shift in Waunlwyd when a large pan dropped out on a packer seriuosly injuring him, it didn't have far to drop as the gobside height was only 2'9" had it been higher he wouldn't have survived Pigeon.

Mikej
These "bellstones" which occurred at intervals in the sandstone strata immediately above a coal seam would not have been of volcanic origin. They are sedimentary rock deposits rich in the iron mineral haematite (Fe2O3). They built up within the sand-rich sediments as these spread over a flood plain or estuarine area during one of the periodic inundations that interrupted the forest environments of these areas un the Upper Casboniferous period of geologic history. They are a kind of "nodule" deposit and grew up as a quantity of iron rich solution precipitated within the accumulating sand and mud.
They would be heavier than the surrounding sandstone because of the higher density of the haematite compared to the sandstone; yes, certainly very dangerous because of their propensity to fall from the rock of an adavancing tunnel, and not always easy to spot in advance before digging revealed their presence.
Hope this is useful
Mike

Thanks for that guys.

I have read reports from some USA mining papers that these 'stones' are the remains of footprints made by Dino's in the peat before burial by flooding etc. These prints fill-in with the upper layer material and then intrude into the seam.

So you may have had your block knocked-off by a size 10 Dino foot!

I'm now trying to re-find the various links.


and now thanks to Google:

[homepage.mac.com]

" Figure 2. Coal mine in the Kenilworth Coal, near Kenilworth, Utah, east of Helper, showing numerous overlapping round-bottomed
dinosaur footprint casts extending down from the roof. Here, the roof’s texture of irregular-shaped lumps extends down from the
surface as far as 30 cm. Few distinguishable foot prints can be identified, but innumerable toes, heels and partial footprints overlap
one another randomly. The swamp surface had been heavily bioturbated, or “dinoturbated”. "

and

[www.unis.no] for some pictures.

You boys were working under a Dinosaur's belly all those years... ;)

Hwyl,

J

( and for the pedantic: I'm using the term 'Dinosaur' quite loosely... )

Sadly,nothing like Pan`s

The strange thing about " Bell stones" is that certain mines are v badly affected while other never have them. Someone who used to call in a pub in Llwynhendy used to bring small ones in from Betws, they used to be on a shelf behind the bar, they were strange looking things, like small perfect bells, others looked more like flying saucers. I never saw one at Cynheidre.

[kb.osu.edu]

I wonder what other fossils miners found and what they thought they were?
As a kid we'd spend hours breaking-up shale on the tip to find the fern imprints inside. ( which I never kept... bl**dy typical of me!)

There are other reports of spectacular fossil finds in other pits. Here in Belgium there were [en.wikipedia.org] section 3:2

So I wonder what was found under our valleys, if anything?

Hwyl,
J

In Lancashire we called them Pudding Stones, they where usualy ironstone, round with a lens shaped section. The seam that I did my training in The Plodder had them above the top coal, we used to leave a foot of top coal when shearing due to a weak roof so we did not see them often.

Like Phil mentions,in some mines you would`nt find them.

The Glyngwilym seam in the Swansea Valley was the only seam i encountered them in,out of 6 other seams i have worked in.

We called them Pan`s or Padell in Welsh,they were Round in this seam,and only visible with a good eye,they had a thin layer of coal around the circumference,and over the top ,enabeling them to just drop out,sometimes the coal used stick to the base of these Pan`s,so one had scrape the coal off the Roof in the face to see if there was a Pan above

The biggest i`ve seen was over 4ft across,thank God,not in my face.

Bells was found in the bench coal seam in Warwickshire they always had a band of coal around them about half an inch thick.Like has been said they was very heavy and hard but if they was left in wet or damp conditions they would eventually start to soften and turn into a clay like mass.

I should have said when they dropped out and was left in the side of the road in damp or wet conditions,sorry

Exprienced quite a few in the No2 Rhondda seam.

Evil things,always strapped a flat across them.

There's a photo I took of a bell at the Llanerch Colliery, Pontypool in 1983 on the link below.

[www.flickr.com]

Would these things only break through at the face area, or would they also come down between the rings in roadways??

Generally they were found in the roof immediately above the coal seam.
They were particularly dangerous because when testing the roof it would sound solid owing to their thickness, also, because of the shiny surface between them and the rest of the roof they could drop out without warning.

While walking on land above Abercrave that had been reclaimed from opencast,you came across these iron stone nodules quite frequently and marveled at their weight for size,as john said,in the coal face above the coal seam,real sneaky B******d if you were realy observant you could make out the very thin coal deposit around the edge of these bells,in Aber they were called in welsh Polsen.

Were these the same ironstone nodules that contained Millerite? I have only seen them on Coedely tip but apparently they were well known in the South Wales coalfield. Millerite is extraordinary stuff - looks like thousands of fine needles.

Ten-out-of-ten to Caiman.
A search on Google took me to an excellent website page about Millerite form the National museum of Wales.
Millerite is a Nickel Sulphide mineral which occurs quite frequently within the clay ironstone nodules in the South Wales coalfield. It has been reported from many mines and opencast sites and NMW Geology section has a nember of specimens.
It has a density of 5.3 to 5,5 which is quite heavy, and occurring within the Haematite and Limonite Iron Oxide compounds dominating these Bellstones which both have densities of approx 5.5 depending on exact compositon, it all adds up to the really dangerous mass of these if falling from above
Mike
PS I'm sure Steve Dumpleton could add considerably to explaining their method of formation within the kinds of rock layers above coal seams where those of you in the mining industry have met them at first hand.

loads of the things in bettws we also called them polsen.some of the old colliers from the old pit called them pans . when we were on pillar and stall. you would hear them dropping from the roof with a thud. remember thinking (if they catch you its gonna hurt) safest way was to set a post under them.

Stuart.
When did Betws work pit &stall.

Last going off Nogin, as a "private mine".

In Deep Navigation,Taff Merthyr, Trelewis Drift & Tower they were called "Balls of Mine"

Quote
jasper
In Deep Navigation,Taff Merthyr, Trelewis Drift & Tower they were called "Balls of Mine"

Same in the celynen north ,ball o'mine,or minestones.

Norman ,wy da.

We had a complete tree trunk at Cynheidre in Cross Measure two. Lots of students came down to see it. The National museum of Wales produced a book in 1982 of fossils found in Wales, many of which were from the coal mines.

Phil,

Was it kept or was that also discarded?

Hwyl,

J

Did find many (not big one's) coming up from Ammanford when we were lad's, never thought of keeping them.

I think it was just left there when the pit closed. That district had closed some years before anyway. There may be some pics floating about.

What faces were down Cross 2? When did it finish coaling? Thanks

Gareth, Cross measure Two was the district that 6 men lost their lives in the 1971 outburst. It had faces on both the 560 and 660. The last face to work on the 560, (where the tree was) finished in 1977, Panel 17A. The Panel 13 was the face which was acting has a return for the heading that the outburst occured in breach of the outbust code. These faces were all in the Big Vein. It was a very productive district (for Cynheidre) Panel 1, 3, 5, 7,9, 13, 15, 17 and 17a.

Thanks Phil