84 
MR.  H.  M.  BECHER  OR  THE 
[Feb.  1893, 
3.  The  Gold-quartz  Deposits  of  Paharg  (Malay  Peninsula).  By 
H.  M.  Becher,  Esq.,  F.G.S.,  Assoc.R.S.M.,  Assoc.  Mem.  Inst.  C.E. 
(B.ead  November  9th,  1892.) 
[Abridged.] 
The  Gold-quartz  formation  of  Pahang  traverses  an  extensive  series 
of  sedimentary  rocks,  of  which  the  low  hill-country  lying  on  the 
eastern  side  of  the  granitic  mountain-axis  chiefly  consists.  These 
rocks,  probably  of  Palaeozoic  age,  are  for  the  most  part  thinly-bedded 
slates,  with  some  sandstones,  and  fewer  dark-coloured,  impure 
limestone-beds.  Locally  they  are  more  or  less  metamorphosed 
and  contorted  ;  quartzites,  and  micaceous  and  other  schists,  often 
intervening  between  the  slate-series  proper  and  the  greater  igneous 
rock-masses. 
Generally  the  strata  are  regularly  and  evenly  bedded,  with  a  pre¬ 
vailing  strike  approximately  north-and-south  ;  they  dip  at  steep 
angles,  mostly  eastwards,  from  which  it  would  appear  that  they 
have  been  subjected  to  an  upheaval,  due  to  intrusion  of  the  central 
granite.  Other  upheavals  are  traceable  to  syenitic  intrusions,  which 
form  lesser  hill-ranges  between  the  backbone-chain  and  the  eastern 
coast :  while  numerous  dykes  of  trappean  rock  have  caused  minor 
local  disturbances.  There  are  not,  to  my  knowledge,  any  indications 
of  eruptive  volcanic  action  in  Pahang,  or  in  any  other  part  of  the 
Malay  Peninsula. 
Besides  the  extensive  slate-formation,  the  only  sedimentary  rock 
noticeable  is  a  peculiar  crystalline  limestone,  which  apparently  over- 
lies  the  first-named  unconformably,  and  is  found  in  isolated  hill- 
patches,  characterized  by  abrupt  vertical  cliffs  and  numerous  caves. 
All  the  alluvial  formations  appear  to  be  of  quite  recent  origin, 
and  to  have  been  undisturbed  since  the  commencement  of  their 
deposition. 
Although  the  Gold-quartz  formation  in  Pahang  is  most  frequently 
associated  with  certain  characteristic  dark- grey  and  black  slate- 
rocks,  it  is  not  confined  to  these,  but  is  also  found  in  other  sedi¬ 
mentary  strata,  extending  indeed  to  the  metamorphic  rocks,  and  in 
some  places  even  penetrating  the  adjacent  intrusive  syenite.  It 
has  not,  however,  been  traced  in  any  connexion  with  the  main 
granitic  formation,  which  is  generally  considered  to  be  the  matrix 
of  another  system  of  metalliferous  deposits — namely,  the  cassiterite- 
veins  which  have  produced  the  vast  expanse  of  the  alluvial  tin-fields 
of  the  4  Straits.’  Very  little  is  yet  known  of  the  nature  of  the 
Malayan  Gold-quartz  deposits,  and  further  researches  will  be  needed 
before  definite  conclusions  can  be  safely  drawn. 
For  the  purpose  of  present  description  the  quartz-deposits  in  the 
solid  rock  may  be  divided  into  two  classes,  though  it  is  difficult  to 
draw  the  line  very  definitely  between  them,  and  some  deposits 
