GemologyOnline.com
https://www.gemologyonline.com/Forum/phpBB2/

Blue john stone
https://www.gemologyonline.com/Forum/phpBB2/viewtopic.php?f=6&t=25183
Page 1 of 1

Author:  offimatrix [ Tue May 21, 2019 4:08 pm ]
Post subject:  Blue john stone

"Blue John stone" Routh on matrix from Castleton Derbyshire UK close to where i live.

About the Stone:
Blue john stone is only found in cave mines at Castleton Derbyshire uk
Blue john is a rare Fluorite that forms blue to dark purple band rings
or veins.
Was used in 18th to beginning of 19th century for making huge vase's or ornaments.
Now a days, Made into small jewellery.

Blue john is stilled mined in small amounts from "Treak cliff cavern"
No large veins of Blue john exist any more with been over mined and only small pockets are now found.

Stone: Blue John - Type of Fluorite.
Colour: Blue. Dark purple. Yellow. Pink. Red. Black. Green. Colour less.
Refractive Index: 1.43
Relative Density: 3.2
Hardness: 4
Crystal group: Cubic
Tenacity: Brittle
Origen: Castleton Derbyshire uk

PS: Specimens I have I got way back in late 80s and stored away till just recently
got out to take photos off. Never weighed them just stored away. There was mined
from "Treak cliff cavern".

Attachment:
1.jpg
1.jpg [ 1.56 MiB | Viewed 453 times ]

Attachment:
2.jpg
2.jpg [ 1.54 MiB | Viewed 453 times ]

Attachment:
3.jpg
3.jpg [ 1.51 MiB | Viewed 453 times ]

Attachment:
4.jpg
4.jpg [ 1.67 MiB | Viewed 453 times ]

Attachment:
5.jpg
5.jpg [ 1.25 MiB | Viewed 453 times ]

Author:  offimatrix [ Sat Aug 03, 2019 2:46 pm ]
Post subject:  Re: Blue john stone

An old video of blue john 1963.

Author:  Barbra Voltaire, FGG [ Sat Aug 03, 2019 7:30 pm ]
Post subject:  Re: Blue john stone

Oh, that film is adorable. :smt055

Author:  johngemo [ Mon Aug 05, 2019 7:06 am ]
Post subject:  Re: Blue john stone

Film?
Did someone eat a link?

When I first saw the top post I went away to look for info on this stone.
(I was looking for sources of UK gem materials at the time)
I did find a small shop still selling ash trays and other stuff made
from blue john - I cant find the link right now but this is an
interesting page of info if you're interested in flourite mines in the UK:

https://www.aditnow.co.uk/Database/?country=232&zone=20&type=1&mineral=16&page=1&records=1000

There are far more mines than I imagined there would be (we are a very tiny country after all)
I'm not so sure I'd class blue john as a gem stone myself - It seems to fall more into a class
like fine granite - nice when worked and very attractive but not so gem like.
Am I way off field there?

Author:  offimatrix [ Mon Aug 05, 2019 12:19 pm ]
Post subject:  Re: Blue john stone

johngemo wrote:
I'm not so sure I'd class blue john as a gem stone myself - It seems to fall more into a class
like fine granite - nice when worked and very attractive but not so gem like.
Am I way off field there?


I see Blue John more as a ornament then a gem since it use to be made in to bowls and verses but now
the blue band window is shown in jewellery or in to low grade purple jewellery.
Its rare in its own right as its only found there in that 1 location.

The bands of blue rings you see, Or to Low grade Blue John that looks much like amethyst which i got just a week
ago for a specimen.
Attachment:
1111.jpg
1111.jpg [ 1.23 MiB | Viewed 192 times ]

Attachment:
222.jpg
222.jpg [ 852.53 KiB | Viewed 192 times ]

Attachment:
111222.jpg
111222.jpg [ 1.35 MiB | Viewed 192 times ]

1705 grams

Attachment:
3333.jpg
3333.jpg [ 1.75 MiB | Viewed 192 times ]

Author:  johngemo [ Wed Aug 07, 2019 4:55 am ]
Post subject:  Re: Blue john stone

Nice rocks - I wonder how much of it is left?

There's quite a few things that seem to only be found in very few or one
location - (The sort of thing that interests my research gene)
Maw sit-sit is another curious one that's quite different from the stuff
surrounding it and only found in one specific place.
(I feel a book theme coming on ...)

Author:  offimatrix [ Mon Aug 12, 2019 4:01 pm ]
Post subject:  Re: Blue john stone

I think there's 17 veins with a new one that's found in 2015.
There's only small pockets left with the new one now been largest, Also
every vain has its own characteristics so a miner can tell which vain from the 17 the
blue john is mined from if there see it.

Page 1 of 1 All times are UTC - 4 hours
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group
http://www.phpbb.com/