15
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19
TABLE VI
+
TO MOTT WOU I Page 41 of 662 CONSUMPTION OF ANHYDRITE IN UNITED KINGDOM
(tons) SELİNDO
onli
Sulphate of
Sulphuric
Ammonia
Acid
Other .uses
Total
1944 (10 months)
518,863
128,502
05/29,476
676,841
1945 1946 1947
...
634,837
161,055
130,31,047
732,648
178,172
21,637
826,939 932,457
717,321
154,892
1.15,847
888,0601 CHI
BALL CLAYS
58. The true ball clays are highly plastic, white-firing, lake deposits of Eocene age, and are found in large amount in Devonshire and in Dorset- shire. The term "ball" derives from the old method of winning the clay by cutting the floors of open pits into cubes or "balls" of about 10′′ side.
the-dan ye hun woodly terroim bila ad o 18sqq
1
59. The industry comprises about 14 companies employing a total of over 900 men ; both open-cast workings and small mines are in operation. Hand-getting is usually essential in working the clays to avoid the danger of contamination, and as a result a high degree of recovery is possible approaching 100 per cent. in the open-casts, and from 75-95 per cent in the pits. we drive dhuna bas ToogoliH ja 1800 od of abalwers abod Ok whiquor at undle alift bnals D sili ka nei za „fordw done mi visi25
Production and Uses
Uses larm og levecim to pinsup Isto od 72slim
o Imsaim
it Stop Prot (08.E tunde 2nuz lorsuit will) comb 60. The production of whiteware clays in Devonshire and Dorset at the present time is about 160,000 tons per annum, and of stoneware and re- fractory clays 125,000 tons, details of which are contained in the table below. The clays find a firm export market at all times, in addition to the large home demand. imseng othbedas to vingup sdi to slachto Bustobro blute verum a tart bermotai OTE ow
DEB wod
otv
TABLE VII
MIDI 10
sit mustas simman o BALL CLAYS 1947ins te wyvern wall A 127
several orod b.reindrow sw u
(tons)
Production unisoma egia od:
Sales and oW JC
Stoneware
Stoneware Sou bedakandlagani
Whiteware and Whiteware beak and whi
weltberute Jud Refractory m
Refractory
Home
South Devon 297,227
82,579: 0040,053
Export
50,538
Home
Export
36,651,37,080-
14,226:
Dorset
45,543
North Devon
Page54,99 of 6626,165hlu84,264
11,633
31,953
5,407 38,804
9.023
7,460
13,661, 2,057 11.917
fire
1,297
67,021 Page2,429 of 6602434
16
61. They are used in the pottery industry to impart plasticity and other properties to the bodies used2for general earthenware, sangey4ware, glazed and other tiles, electro-ceramics, porcelains and high-grade refractories, the particular use being determined by the properties of the individual clays. Am important quantity of clay is now used in bonding abrasive wheels and blocks to dignol a 1990 ayelu aldadiow 'animoo wetplooief boa disoM
guin bar 62. Broadly, the clays are divisible into three groups: Div alun kech (i) Black Clays highly aluminous types, characterised by the presence of varying amounts of carbonaceous matter, chiefly of lignitic moodall nature. In certain cases these clays approach low-grade lignites. canod These
beaLOV clays are found mainly in
found mainly in south Devon. IE TOMAR. PONSOOL UNI GR. AL. 20 soiui visviterso
(ii) Blue Clays highly aluminous types, coloured in various tints of Landi zhonjile red, brown, blue, grey, up to, creamy white, the colour being determined by the amount and nature of the iron compounds present. These clays are found chiefly in Dorset, but also in north and south Devon.400
(iii) Stoneware and Refractory Clays Stoneware, clays are characterised vistages suitby high silica content (from 60 per cent, upwards) the excess exonasida okover that necessary for the clay mineral being present largely as quartz. These clays are also used largely for the manufacture „anor: 0007001¤f stoneware goods including drain pipes. Clays used in the vidado en refractories industries comprise not only certain stoneware clays rol Abadong but also blue and black clays of high iron content. There is no essential relation between the colour of the raw clay and that of the fired product but the black and blue clays, usually known as "whiteware" clays, when fired to 1100-1200° C. give a product whose colour varies from white to cream.
•
O'q 90 003
265
beenas vidadong evelo siswotiɗw oldeulov izom sdi lo eprisen SHT ON Resources doum 2 303 atomsziupen ebat hogas bas smod oldatoiberg tis b63 There are three areas in which the clays occur in sufficient amount to be worked, namely-line baasd astedites se seod) : syswoll 24091 (i) South Devonshire, in the neighbourhood of Bovey Tracey and 109129 ONE Newton Abbot, especially the lattery off of bisgan quvch birow ved *bai (ii) North Devonshire, on the low-lying tract of country between the villages of Peters Marland, Meeth and Petrockstow in the Mere Tano ai AionValley a tributary of the Torridge 10-15 miles south of ladyBideford.no bonnel of blues guidhow yazsoon stedw Jerh (iii) Dorsetshire, around Wareham and Corfe Castle.
SOUTH DEVON U
maño 90 binona kol
5764. Clay working in this area is reported to have begun about 1730. The area in which the clays soccur is roughly a narrow ellipse extending from Bovey Tracey down to Newton Abbot and having an overall area of 18-20 sq miles. The main workings are situated on the S.E. margin near Kingsteignton under a cover of up to 30 ft. of Recent sand and gravels. As many as 30 clays beds, ranging from 1 to 11 ft. in thickness are recorded but they are often highly distorted and discontinuous. Geologically the beds occur in a basin, the depth of which has been proved to be at least 700 ft.
wwerb ma yech didymont jednot ugutos solve dig 65. The reserves of whiteware clay in the area are very great. The clay appears to run at about 1,500 tons/acre ft. which, assuming an average thickness of 10 ft. of workable clay over the southern half of the basin