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Barytes and Witherite

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Barytes and Witherite MEMOIRS F TH OL I AL S VE O E GE OGC UR Y. SPECIAL REPORTS ON THE MINERAL RESOURCES OF GREAT BRITAIN. O II - BA YT D IT E V L . R ES A . N W H R ITE G . WIL B E SON . O . A S . STWOOD V , , T , . W . CO K B O C . S O . A A . Y M . S O . R P , , D WR , , AND BE . SON D . S c T RO RT , . WIT H CON TRIB U T ION S B Y H . E G . IN S D , T H ER D E D ET IO N . ’ PUBLISHED BY ORDER OF THE LOR DS C OMMISSIONER S OF HIS MAJESTY S E Y TR ASUR . Q t M EOND ON P “ RINTE UN E TH E AUT RI Y’ D D R H O T? OF H IS MAJE ST S STATIO NE RY O FFICE T o b e pumfimésed from E S TAN L D . O R , T and 1 4 LON G »E ERE L N D F D , X , O ON W HO 2 , , . A . JO HNS TO LT D D W ST . AN RE S A E IN B G K W QU RE , UR H ; * H O E S I IS < OO ) DG , F GG m 20 , N S S S T T a k A AU REE , n d 1 7 a n d 1 8 F D IC K S T , RE ER . REET DUB LIN ; or rom a n A en t for th e s a l e of O rdn a n c e S ur f y g vey M a p s ; or through a n y sell er r m oo , o th e IRE CTO R ENE RAL D B k f D G , O R N AN CE SUR VEY S T PT N OU HAM O . P ' m ce 33 . N et. E PR FACE . of i 1 9 1 5 The first edition this memoir , wh ch was published in , wa s E . written by R . G . Carruthers , T . astwood , G . V Wilson , E Br m ehea d . A . o R W Pocock , D . Wray , H . Dewey , and C . N . ‘ 1 9 1 6 c a the . In se ond edition appeared , by same authors The exhaustion of the second edi tion afforded an opportunity for a m t nf of co ple e revision of the i ormation , but several the authors d i m of earlier e itions were no longer available , and the r na es are , di m All accor ngly, O itted from the title pa ge . the principal t of t a n d mines have been revisi ed , and the accounts outpu M i . r work ngs brought up to date as far as possible . Wilson t t M E con ribu es the chapter on Scotland ; essrs . astwood and Wray describe the deposits of the six northern counties ; Mr . w the of Pocock deals ith mines Shropshire , Wales and the Welsh M r . t e Border ; Robertson supplies h account of Derbyshire , M r . M and Dines that of Devon and Somerset ; essrs . Wray and m m Dines also describe so e of the ines of North Wales . We have in all cases to acknowledge our indebtedness to the owners a nd managers for their cordial co - operation during the Mr i s . v sits to their mines . To Col . J . V . Ram den , and he M . t T C F Hall of Shropshire ines , Ltd , we are specially indebted for m aps and reports of the - m ines of Shropshire and M m the ontgo eryshire . Our thanks are also due for great M m b . assistance rendered in Cu berland y essrs Reynoldson , Robinson , Davis and Porter . The work of editing the memoir has been carried out by Mr . Henry Dewey . OHN . E TT J S FL , D r f i recto . Geological Survey O fice , 2 8 erm n , J y Street , I S . W . London , 6th S e tem b er 1 92 1 p . fl d Q jm w é u J/W Z T E T C O N N S . PAC E PREFACE B Y TH E DI R ECT OR CHAPT ER — IN TR D T I N . C a ra cters of th e n eral s . S ources of I . O UC O h Mi mm rc l ses n d o e U . I ustr a l S upply . C ia i Notes - TH E IN S O F T H E S IX N T N C N T I S II . M E OR HER OU E l n d m er a . 5 . 2 . a m 1 1 . Nort u ur . 0 . h b , p D h , p 24 m r a . 4 m orla n 4 2 . C e l d . s d . 3 . u n e t b , p . W , p r 5 1 h r Y r s e . La n c a 6 s e . 3 . 5 . o 6 k hi , p i , p II —TH E IN S O F R B I P S I AND T H E S I . - M E DE YSH RE , SHRO H RE WEL H BOR DER ’ 4 2 r re . 6 . S ro s re a n h 1 . e s d t e ls D by hi , p h p hi We h d r or e . 69 . B , p ' IVE— T H E MIN ES O F WALE S AN D T H E WE S T O F E N GLAN D 4 Nort a les . 8 2 . Cen tra l a n d S 1 . out a les h W , p h W , p . 8 8 . re 94 S om r 3 . e on s . e set D v hi , p , — TH E IN S O F S TL N D V . M E CO A INDEX a: Wt 1 558 9—S 1 000 Item fi ILLUSTR ATIONS X I TE T F GUR E . —M a f th e Bla i rl o i e e n s I . 1 o F G . p g V i S PLAT E . PLAT E — O ut ut of ar um n era ls rom the lea di n di str cts of I . p B i Mi f g i E n l an d a l es a n d Ir a n d a ci n g , W , el f g ' — a l O ut ut of a r um n erals i n the Un i ted n dom II . T ot p B i Mi Ki g , a n d T ota l Im p orts fa ci n g I — O ut ut of t er te i n the Un ted ndom II . p Wi h i i Ki g —M a of a r tes a n d t er te a rea s of th e Nort of E n la n d IV . p B y Wi h i h g fa ci n g —M a of ar tes a rea of er s re i n V . p B y D by hi fa c g 64 —M a of a r tes n es of S r o s re Nort a n d Cen r VI . p B y Mi h p hi , h t a l Wa l es fa ci n g 69 BAR YTES ‘ AND WITHER ITE E CHAPT R I . INTRODUCTION . H TE S O F TH E MINE ALS C ARAC R R . or Ba SO Barytes , barite , heavy spar barium sulphate ( Q) ° 65 7 . B c ontains per cent of barium oxide or baryta ( a O ) . It is l e a rhombic mineral , common y found in massive platy aggregat s , e i as ly cleaved , with either straight or curved surfaces , but , exceptionally , an earthy or a fibrous banded habit may be a . ssumed (Derbyshire) When able to grow freely , beautiful t . crystals result , Often abular , with deeply bevelled edges In c olour the mineral , when pure , varies from opaque white to - a water clear , but is frequently stained , especi lly with red or brown ferruginous compounds , which may be either superficial or disseminated throughout the spar . 3 3 - 5 Barytes has a white streak , and in hardness ( to ) is s i m h imilar to , or sl ghtly greater than , calcite , a ineral with whic it is commonly associated an d sometimes confused ; but barytes is n early twice as heavy as calcite (the specific gravity being 4 ° and it does not efi ervesce with acid . - - In this country barytes is pre eminently a vein min eral . It m m - is a co on constituent of mineral lodes , especially those carrying - t lead and zinc ores , and in these cases is generally associated wi h of fi uors a r varying proportions calcite , quartz or p , though many veins are known in which barytes occurs practically alone . In ’ “ Germany (the world s chief producer) most of the spar also comes m from ineral veins , but the United States have extensive surface i m - deposits in which it is a residual product of l estone weathering . These latter deposits can be paralleled on a minor scale at M fi eld . Nut i n Bradwell oor , Derbyshire (p At , Surrey , barytes occurs in isolated crystalli ne masses embedded i n ’ ” fuller s earth .
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