MYSTERY OBJECTS

[Stanley]

Sorry but no. Clue, a down-stream process of Iron smelting.

[StoneRoad]

Making steel or another alloy or a purer iron ?

[Stanley]

Sorry, no. It's a by product..... I'll give it another day.

[chinatyke]

I'm guessing they are using slag waste with limestone to make bricks or possibly refractory bricks. Only thing I can think of!

[Stanley]

You are so close China! Stay on that track. Think useful by-product.

[Tizer]

Are you thinking of sulphuric acid made from the sulphur dioxide byproduct of iron smelting?

[chinatyke]

This looks like a low tech operation and I'm guessing again. Lime and slag were used as a dressing to improve farmland. Could this be how it was prepared?

[Stanley]

Again, very close. Ground basic slag was a very widely used agricultural fertilizer. They are melting purified slag to make slag wool insulation. Legend is that some smart person saw molten slag run over a steam pipe that had a leak in it and the result was long streamers of glass like filaments. That started an industry, very good insulation, totally non-flammable and not a good material for vermin infestation. Would have been a very good insulation for cladding high rise blocks of flats!
Next one?

[chinatyke]

I've never heard of that use for slag. I've heard of mineral wool insulation, is that what this was called? I assumed it was glass fibre.

[Stanley]

Not sure China. Slag wool was the precursor of glass fibre insulation. It was coarser and had little hard lumps in it, of course the slag was a form of impure glass. One thing I noticed when installing it was that it didn't irritate your throat as badly as fibre glass. I hated that stuff!

[Tizer]

`Mineral wool insulation is made from molten glass, stone or slag (industrial waste) that is spun into a fibre-like structure and which creates a combination of properties that no other insulation material can match. There are two types of mineral wool product: glass wool insulation and stone wool insulation.
Inorganic rock or slag are the main components (typically 98%) of stone wool. The remaining 2% organic content is generally a thermosetting resin binder (an adhesive) and a little oil. Glass wool products usually contain 95% to 96% inorganic material.
Stone wool is made from volcanic rock, typically basalt or dolomite, an increasing proportion of which is recycled material in the form of briquettes. Mineral wool made from blast furnace slag (waste) is sometimes known as slag wool.
Glass wool is made from sand or recycled glass, limestone and soda ash; the same ingredients as for familiar glass objects such as window panes or glass bottles.' Taken from the web page: EURIMA

[I have to take issue with their reference to dolomite. It isn't a volcanic rock, it's like limestone (calcium carbonate) but with some of the calcium replaced by magnesium which makes it a bit harder.]

[chinatyke]

Stone wool is made from volcanic rock, typically basalt or dolomite, an increasing proportion of which is recycled material in the form of briquettes.

[I have to take issue with their reference to dolomite. It isn't a volcanic rock, it's like limestone (calcium carbonate) but with some of the calcium replaced by magnesium which makes it a bit harder.]

Thanks Tiz.

I think they have got their punctuation wrong and wouldn't have meant to suggest dolomite was volcanic:

Stone wool is made from volcanic rock, typically basalt, or dolomite...

[Stanley]

What's this?

[Gloria]

Looks very interesting, is it for checking the concentricity of an object?

[Tizer]

Stone wool is made from volcanic rock, typically basalt or dolomite, an increasing proportion of which is recycled material in the form of briquettes. [I have to take issue with their reference to dolomite. It isn't a volcanic rock, it's like limestone (calcium carbonate) but with some of the calcium replaced by magnesium which makes it a bit harder.]

Thanks Tiz. I think they have got their punctuation wrong and wouldn't have meant to suggest dolomite was volcanic:
Stone wool is made from volcanic rock, typically basalt, or dolomite...

I agree with you China that the comma should be there so that dolomite isn't implied to be volcanic. But there's another issue here - do they really mean dolomite? It's calcium magnesium carbonate, it doesn't contain any silica, it's relatively soft and it dissolves in acid. it doesn't sound to me like the type of material for making mineral wool. Quite unlike basalt which contains quartz and other very hard and resistant minerals. When you heat dolomite it doesn't melt it decomposes into calcium oxide (quicklime) and its magnesium equivalent, magnesium oxide.

I've looked beyond the EURIMA web site and find other mineral wool pages, e.g. the Knauf web site, saying almost exactly the same as the EURIMA page. It makes me wonder if they're all perpetuating a mistake. I wouldn't be surprised if they are confusing dolomite with dolerite which is similar to basalt in composition, structure and properties and is also volcanic in origin (to a precise geologist it is not truly volcanic but is an igneous intrusive rock - it's formed from magma squeezed along fissures and doesn't get blown out of a volcanic cone but a layman would probably call it volcanic). Geologists are forever troubled by the woolly nomenclature used in the masonry trade. Granite is a good example. In the stone trade any hard black stone gets called `granite' yet true granite is not black and not homogeneous. It's a very specific mixture of quartz, feldspar and mica with a characteristic appearance.

[StoneRoad]

Stone wool is made from volcanic rock, typically basalt or dolomite, an increasing proportion of which is recycled material in the form of briquettes. [I have to take issue with their reference to dolomite. It isn't a volcanic rock, it's like limestone (calcium carbonate) but with some of the calcium replaced by magnesium which makes it a bit harder.]

Thanks Tiz. I think they have got their punctuation wrong and wouldn't have meant to suggest dolomite was volcanic:
Stone wool is made from volcanic rock, typically basalt, or dolomite...

I agree with you China that the comma should be there so that dolomite isn't implied to be volcanic. But there's another issue here - do they really mean dolomite? It's calcium magnesium carbonate, it doesn't contain any silica, it's relatively soft and it dissolves in acid. it doesn't sound to me like the type of material for making mineral wool. Quite unlike basalt which contains quartz and other very hard and resistant minerals. When you heat dolomite it doesn't melt it decomposes into calcium oxide (quicklime) and its magnesium equivalent, magnesium oxide.I've looked beyond the EURIMA web site and find other mineral wool pages, e.g. the Knauf web site, saying almost exactly the same as the EURIMA page. It makes me wonder if they're all perpetuating a mistake. I wouldn't be surprised if they are confusing dolomite with dolerite which is similar to basalt in composition, structure and properties and is also volcanic in origin (to a precise geologist it is not truly volcanic but is an igneous intrusive rock - it's formed from magma squeezed along fissures and doesn't get blown out of a volcanic cone but a layman would probably call it volcanic). Geologists are forever troubled by the woolly nomenclature used in the masonry trade. Granite is a good example. In the stone trade any hard black stone gets called `granite' yet true granite is not black and not homogeneous. It's a very specific mixture of quartz, feldspar and mica with a characteristic appearance.

I think that Dolomite should actually be Dolorite - another igneous rock like basalt.
https://en.wikipedia.org/wiki/Diabase

As has been said Dolomite is a sedimentary rock ...

[Stanley]

Gloria, you are correct so far but there is more to it than that.
The children are off piste at the moment solving the internet's problems.... (Clever buggers!)

[Gloria]

Would you use a dial indicator attached to a clock stand with a magnetic magnetic base in conjunction with this?

[Stanley]

You could do but it would never be done, far more hands on and rack of the eye than that Gloria.

[Gloria]

Would rack of eye be used in conjunction with L shaped pointer seen at the bottom of the fixture?

[chinatyke]

Is it for truing wheels with spokes, for example bicycle wheels?

[Stanley]

It would Gloria but while you were homing in China has upstaged you with the right answer, it's a frame for lacing up, spoking, trueing and balancing bicycle wheels. How could he do this to you.....

[Tizer]

I think that Dolomite should actually be Dolorite - another igneous rock like basalt.
https://en.wikipedia.org/wiki/Diabase
As has been said Dolomite is a sedimentary rock ...

Agreed. (Diabase is the US name for what we call dolerite in the UK).
I've written to the Mineral Wool Industry Manufacturers' Association (EURIMA only give a Brussels phone number on their web site) to ask for clarification. No reply so far.
Later...Some more research on the web shows that dolomite can be used as a flux additive when making glass wool and can be incorporated in mixes using dolerite or basalt. So, dolomite isn't an alternative to the igneous rock but can be used to bulk it out.
Phew, sorry for going off topic!

[Gloria]

It would Gloria but while you were homing in China has upstaged you with the right answer, it's a frame for lacing up, spoking, trueing and balancing bicycle wheels. How could he do this to you.....

[chinatyke]

It would Gloria but while you were homing in China has upstaged you with the right answer, it's a frame for lacing up, spoking, trueing and balancing bicycle wheels. How could he do this to you.....

Sorry Gloria. You can have the Brownie points.

I thought it was for bike wheels immediately I saw it but somehow it didn't look big enough. I was trying to think of alternatives that would fit in with Stanley's work. I'm surprised Ian didn't jump in with the answer.