﻿88 
  Thirtieth 
  Report 
  on 
  the 
  State 
  Museum. 
  

  

  the 
  labradorite 
  has 
  disappeared 
  leaving 
  angular 
  fragments 
  of 
  

   quartz 
  projecting 
  ; 
  42 
  is 
  similar 
  to 
  the 
  three 
  preceding, 
  but 
  owes 
  

   its 
  exceptionally 
  high 
  gravity 
  to 
  many 
  included 
  iron-lime 
  

   garnets, 
  which, 
  in 
  conjunction 
  with 
  hornblende 
  and 
  weathered 
  

   labradorite, 
  account 
  for 
  its 
  dark 
  reddish-yellow 
  appearance. 
  

  

  The 
  above, 
  on 
  account 
  of 
  the 
  strikingly 
  stratified 
  arrange- 
  

   ment 
  of 
  their 
  constituents, 
  might 
  be 
  termed 
  Gneissoid 
  Norites. 
  

   Along 
  with 
  them, 
  should 
  be 
  included 
  specimens 
  9, 
  14, 
  15, 
  16, 
  

   17, 
  20, 
  24, 
  29, 
  31, 
  37, 
  57 
  and 
  63. 
  The 
  labradorite 
  of 
  Nos. 
  9, 
  14 
  

   and 
  15, 
  is 
  almost 
  as 
  white 
  as 
  milky 
  quartz 
  — 
  an 
  appearance 
  due 
  

   to 
  partial 
  alteration, 
  and 
  the 
  segregation 
  of 
  minute 
  amorphous 
  

   particles 
  parallel 
  to 
  the 
  stratification. 
  These 
  impart 
  a 
  milky 
  

   aspect 
  to 
  the 
  mass, 
  and 
  obscure 
  the 
  limpidity 
  of 
  thin 
  sections. 
  

   No. 
  14 
  also 
  includes 
  large 
  masses 
  closely 
  striated, 
  but 
  of 
  a 
  

   white 
  vitreo-waxy 
  appearance, 
  in 
  this 
  respect 
  differing 
  from 
  

   the 
  more 
  highly 
  vitreous 
  smoky-grey 
  crystalline 
  aggregates, 
  

   presently 
  to 
  be 
  described. 
  The 
  interstratified 
  black 
  portions 
  

   are, 
  in 
  part, 
  diallage. 
  Their 
  metallic, 
  in 
  some 
  specimens, 
  even 
  

   bronze-like 
  lustre, 
  has 
  caused 
  the 
  names 
  hyper 
  sthene 
  and 
  

   bronzite 
  to 
  be 
  applied 
  to 
  them. 
  They 
  are 
  associated 
  with 
  horn- 
  

   blende, 
  derived 
  from 
  alteration 
  of 
  the 
  diallage. 
  The 
  alteration 
  

   in 
  some 
  cases 
  is 
  nearly 
  complete. 
  Besides 
  diallage 
  and 
  horn- 
  

   blende, 
  specimens 
  16, 
  17, 
  24 
  and 
  31, 
  include 
  almandite 
  and 
  20 
  

   essonite, 
  mostly 
  distributed 
  through 
  the 
  feldspathic 
  base. 
  

  

  Nos. 
  2, 
  3, 
  5, 
  6, 
  7, 
  10, 
  11, 
  19, 
  25, 
  28, 
  31, 
  59, 
  60, 
  62 
  and 
  65, 
  may 
  

   be 
  grouped 
  together 
  and 
  classified 
  under 
  the 
  title 
  of 
  Porphyritic 
  

   Norites, 
  inasmuch 
  as 
  they 
  consist 
  of 
  highly 
  twinned 
  and 
  finely 
  

   striated 
  polysynthetic 
  macles 
  of 
  labradorite, 
  in 
  a 
  coarse 
  or 
  

   finely 
  -granular 
  crypto-crystalline 
  labradorite 
  paste. 
  Although 
  

   this 
  matrix 
  in 
  external 
  aspect, 
  differs 
  so 
  widely 
  from 
  the 
  

   included 
  labradorite 
  crystals, 
  that 
  it 
  is 
  often 
  mistaken 
  by 
  

   mineralogists 
  for 
  some 
  other 
  species, 
  yet, 
  as 
  will 
  be 
  seen 
  in 
  

   Part 
  III 
  of 
  the 
  present 
  article, 
  in 
  specific 
  gravity, 
  composition, 
  

   pyrognostic 
  and 
  physical 
  characters, 
  it 
  is 
  almost 
  identical. 
  In 
  

   some 
  varieties, 
  no 
  other 
  mineral 
  is 
  present 
  in 
  separately 
  visible 
  

   masses, 
  and 
  this 
  species 
  of 
  norites, 
  passes 
  into 
  Porphyritic 
  

   Labradorite. 
  The 
  crypto-crystalline 
  paste, 
  as 
  in 
  No. 
  5, 
  the 
  

   specimen 
  whose 
  complete 
  analysis 
  is 
  given 
  beyond 
  (A), 
  is 
  some- 
  

   times 
  in 
  color 
  and 
  lustre 
  not 
  unlike 
  common 
  yellow 
  wax, 
  thus 
  

   contrasting 
  strongly 
  with 
  the 
  more 
  vitreous 
  bluish-smoky 
  

  

  