170  CONTRIBUTIONS    TO   ECONOMIC    GEOLOGY,  1904.        [bull.  260. 
iron  pyrites,  and  some  rarer  minerals.  Near  the  lodes  are  placerSj 
both  residual  and  alluvial,  and  the  Larger  part  of  the  tin  product  of 
the  region  has  been  obtained  from  them. 
Queensland,  in  the  northeastern  portion  of  Australia,  has  produced 
tin  at  a  number  of  places,  particularly  at  Herberton,  Cooktown, 
Watsonville,  Stanthorpe,  Wild  River,  and  the  Kangaroo  Hills.  The 
only  lode  workings  are  at  Herberton,  Cooktown,  and  Kangaroo 
Hills. 
The  principal  lode  mines  are  at  Herberton,  in  the  southern  part  of 
the  colony,  in  a  mountainous  district,  with  hills  2.000  to  4,400  feet 
high.  The  lodes  occur  chiefly  in  coarse  arkoses  and  quartzites,  and  to 
a  less  extent  in  the  granites,  older  slates,  and  schists.  In  many  cases 
the  lodes  are  replacements  of  the  country  rock  along  fissures.  In 
other  cases  the  tin  appears  in  grains  disseminated  through  apparently 
unaltered  granite  or  porphyry.  The  rock  is  largely  chloritized  and 
serpentinized.  Tourmaline,  wolframite,  topaz,  fluorspar,  bismuthin- 
ite,  stibnite,  galena,  chalcopyrite,  and  magnetite  accompany  the  ore. 
In  the  Stanthorpe  district,  in  the  southeastern  part  of  Queensland, 
gravels  that  have  been  partially  worked  by  hand  for  tin  are  now 
being  successfully  worked  by  dredgers,  although  the  tin  content  is 
small.  One  114-hour  run.  during  which  time  5,500  tons  of  gravel 
were  handled,  gave  5,600  pounds  of  tin  ore.  Another  run  of  251 
hours,  during  which  time  10.000  tons  of  gravel  were  handled,  gave 
3,360  pounds  of  tin  ore. 
Tin  was  first  discovered  in  Queensland  in  1872,  and  the  output 
reached  its  maximum  in  1873,  when  10,010  tons  of  ore  were  produced. 
In  1903  the  production  was  4,153  tons. 
New  South  Wales,  lying  on  the  east  side  of  Australia,  is  the  second 
largest  producer  of  tin  of  the  Australian  region.  The  richest  occur- 
rences are  in  the  northeastern  part,  near  the  Queensland  line,  in  the 
Vegetable  Creek,  Tenterfield,  Deepwater,  and  Emmaville  districts. 
Smaller  deposits  occur  in  the  northwestern  portion  of  the  colony  in 
the  Stanley  Mountains,  in  the  central  portion  near  Melrose  and 
Fifield,  and  in  the  southern  portion  close  to  the  Victoria  line,  near 
Germantown.  Tumbarumba,  and  at  a  few  other  places. 
The  geology  is  in  general  very  similar  to  that  of  the  occurrences 
in  Queensland.  In  the  Vegetable  Creek  district  the  hills  are  formed 
of  granite,  with  some  diorite  and  acid  dikes.  The  granite  is  thrust 
through  upper  Silurian  shales,  quartzite,  and  conglomerate.  The 
tin-bearing  granite  is  supposed  to  be  Permian. 
Tin  veins  occur  in  the  granite  and  other  igneous  rocks,  and  also 
in  the  shales.  They  sometimes  reach  a  width  of  4  feet.  There  are 
also  stock  works  in  the  granite.  Cassiterite  in  the  veins  is  associated 
wuth  quartz  and  feldspar,  and  all  appear  to  have  been  deposited  at 
the  same  time.     The  veins  are  said  to  average  3J  per  cent  cassiterite. 
