﻿72 
  TWENTY-FIRST 
  REPORT 
  ON 
  THE 
  STATE 
  CABINET. 
  

  

  The 
  mineral 
  filling 
  the 
  chambers 
  of 
  the 
  fossil 
  is 
  in 
  this 
  case 
  

   loganite, 
  but 
  the 
  delicate 
  tubuli, 
  which 
  are 
  preserved 
  in 
  the 
  

   Eozoon 
  from 
  most 
  other 
  localities, 
  have 
  almost 
  entirely 
  disap- 
  

   peared; 
  a 
  fact 
  perhaps 
  connected 
  with 
  the 
  removal 
  of 
  the 
  calca- 
  

   reous 
  skeleton, 
  and 
  its 
  replacement 
  by 
  dolomite. 
  

  

  As 
  a 
  vein-mineral, 
  dolomite 
  has 
  been 
  but 
  seldom 
  observed 
  in 
  

   the 
  Laurentian 
  veins. 
  A 
  magnesian 
  carbonate 
  of 
  lime 
  is, 
  however, 
  

   found 
  in 
  two 
  localities 
  in 
  North 
  Burgess, 
  in 
  one 
  case 
  forming 
  the 
  

   gangue 
  of 
  apatite 
  crystals, 
  and 
  in 
  the 
  other 
  of 
  prisms 
  of 
  brown 
  

   mica. 
  The 
  analysis 
  of 
  the 
  yellowish 
  sparry 
  carbonate, 
  in 
  the 
  latter 
  

   instance, 
  showed 
  it 
  to 
  contain, 
  besides 
  carbonates 
  of 
  lime 
  and 
  mag- 
  

   nesia, 
  a 
  notable 
  amount 
  of 
  carbonate 
  of 
  iron 
  and 
  a 
  little 
  carbonate 
  

   of 
  manganese. 
  These 
  complex 
  carbonates 
  require 
  further 
  study. 
  

   The 
  interesting 
  results 
  obtained 
  by 
  Jenzsch 
  in 
  the 
  analysis 
  of 
  a 
  

   similar 
  white 
  sparry 
  carbouate, 
  which, 
  at 
  Sparta, 
  New 
  Jersey, 
  

   forms 
  the 
  veinstone 
  of 
  the 
  red 
  zinc 
  ore 
  and 
  franklinite, 
  deserve 
  

   to 
  be 
  recalled 
  in 
  this 
  connection. 
  He 
  found 
  the 
  spar 
  to 
  contain 
  

   carbonate 
  of 
  lime 
  79.96, 
  carbonate 
  of 
  magnesia 
  1.94, 
  carbonate 
  of 
  

   manganese 
  11.09, 
  carbonate 
  of 
  iron 
  0.60, 
  carbonate 
  of 
  zinc 
  0.58, 
  

   besides 
  5.39 
  per 
  cent, 
  of 
  fluorid 
  of 
  calcium, 
  an 
  ingredient 
  which 
  he 
  

   has 
  also 
  detected 
  in 
  the 
  calcareous 
  spar 
  of 
  several 
  other 
  localities 
  

   (Amer. 
  Jour. 
  Science 
  [2], 
  xxi, 
  197). 
  

  

  Fluor 
  Spar. 
  — 
  Inasmuch 
  as 
  fluorid 
  of 
  calcium 
  enters 
  into 
  the 
  

   composition 
  both 
  of 
  the 
  calcite 
  and 
  the 
  apatite 
  of 
  these 
  calcareous 
  

   veins, 
  we 
  are 
  prepared 
  to 
  find 
  it 
  separately 
  crystallized, 
  as 
  fluor- 
  

   spar, 
  which 
  occurs 
  in 
  several 
  localities 
  among 
  the 
  Laurentian 
  

   limestones 
  of 
  the 
  United 
  States, 
  in 
  veins 
  with 
  scapolite, 
  chondro- 
  

   dite, 
  pyroxene, 
  spinel, 
  and 
  other 
  characteristic 
  species. 
  In 
  Canada 
  

   it 
  is 
  met 
  with 
  in 
  Ross, 
  Ontario, 
  in 
  small 
  purple 
  cleavable 
  grains, 
  

   imbedded, 
  with 
  prisms 
  of 
  apatite 
  and 
  large 
  crystals 
  of 
  spinel, 
  in 
  

   what 
  has 
  been 
  described 
  in 
  the 
  Geology 
  of 
  Canada, 
  pages 
  461 
  

   and 
  463, 
  as 
  a 
  yellowish 
  white 
  crystalline 
  limestone, 
  and 
  which, 
  

   from 
  its 
  mineralogical 
  characters, 
  will 
  probably 
  be 
  found 
  to 
  be 
  a 
  

   veinstone. 
  In 
  addition 
  to 
  this, 
  a 
  small 
  vein, 
  filled 
  with 
  cleavable 
  

   purple 
  fluor-spar, 
  was 
  observed 
  in 
  the 
  vicinity. 
  The 
  purple 
  fluor 
  

   wmich 
  occurs 
  w 
  7 
  ith 
  red 
  heavy-spar, 
  in 
  fissures 
  or 
  cavities 
  in 
  the 
  

   limestone 
  associated 
  with 
  the 
  hematite 
  of 
  Iron 
  Island, 
  in 
  Lake 
  

   Nipissing 
  (Geol. 
  Can., 
  pages 
  456 
  and 
  463), 
  is 
  probably 
  also 
  a 
  vein- 
  

   stone 
  mineral, 
  and 
  I 
  know 
  as 
  yet 
  of 
  no 
  certain 
  evidence 
  that 
  fluor 
  

   occurs 
  as 
  a 
  distinct 
  species 
  among 
  the 
  Laurentian 
  bed-minerals. 
  

  

  