226       AMERICAN  CHROME  IRON  ORE. — ASBESTOS  PAPER. 
trous  granules,  many  of  which,  under  magnifying  power,  appear 
to  be  regular  octahedrons.    There  is  no  appreciable  quantity 
of  magnetic  oxide  of  iron  intermixed  with  the  sample,  nor  of 
other  impurities  which  would  tend  to  lower  the  per  centage  of 
sesquioxide  of  chromium.    The  amount  of  this  latter  constituent 
as  determined  by  Dr.  Genth,  is  stated  to  be  equivalent  to  63 
per  cent,  of  chromic  acid — a  mode  of  expressing  the  value  of  the 
ore  by  the  quantity  of  chromic  acid  produced  on  fusion  with  an 
alkali,  and  not  that  of  the  green  sesquioxide  actually  contained 
therein.    By  a  qualitative  examination  we  have  ascertained  that 
the  proportion  of  chromium  must  certainly  be  very  large,  and 
have  had  at  the  same  time  an  opportunity  of  corroborating  a 
statement  made  by  our  informant  to  the  effect  that  the  mineral 
requires  long-continued  fusion  to  separate  the  whole  of  the 
chromium  in  a  soluble  form.     Ore  of  this  superior  description 
may  be  obtained  in  casks  ready  for  shipment  at  the  rate  of  about 
one  dollar  for  each  one  per  cent,  of  chromic  acid  per  ton,  and 
in  quantities  of  about  200  tons  annually.    It  is,  however,  con- 
sidered more  judicious  to  work  this  ore  in  admixture  with  other 
qualities  which  are  produced  in  greater  abundance, — 1500  tons 
annually, — the  average  composition  of  such  samples  furnishing 
usually  about  50  per  cent,  of  chromic  acid.     The  ore  last  des- 
cribed was  accompanied  by  specimens  of  asbestos,  and  of  paper 
containing  about  one-third  proportion  of  the  same.    The  min- 
eral may  be  procured  from  Mr.  Oudesluys  at  the  rate  of  1|  cents 
per  pound, — a  low  price  considering  the  high  quality  of  the 
article  offered.    The  specimen  sent  is  beautifully  white,  and 
the  fibres  are  long  and  delicate.    It  has  been  tried  in  America 
for  paper-making  and  for  the  manufacture  of  steam-packing,  in 
both  of  which  applications  it  is  said  to  be  very  serviceable.  Its 
property  of  resisting  heat  and  its  bad  conducting  power  would 
render  this  material  particularly  valuable  in  connection  with 
steam  machinery.    The  sheet  of  paper  sent  is  a  portion  of  an 
experimental  manufacture ;  it  burns  with  flame,  leaving  a  white 
incombustible  residue,  which,  with  careful  management,  retains 
the  form  of  the  original  sheet,  the  weight  of  ash  amounting  pre- 
cisely to  30  per  cent.    Characters  written  on  the  paper  with 
ordinary  black  ink  are  still  legible  after  burning. — Ohem.  News, 
London,  Jan.  25f/*,  1862. 
