﻿28 
  SOUTH 
  AMERICAN 
  INDIANS 
  [B. 
  A. 
  E. 
  Bull. 
  143 
  

  

  tion 
  are 
  not 
  uncommon. 
  In 
  the 
  Early 
  Periods 
  of 
  Mochica, 
  Nazca, 
  

   and 
  Tiahuanaco, 
  the 
  painted 
  and 
  modeled 
  designs 
  are 
  pictorial. 
  

   In 
  Mochica, 
  the 
  decoration 
  is 
  truly 
  realistic; 
  and 
  in 
  both 
  Nazca 
  

   and 
  Tiahuanaco, 
  the 
  design 
  figures 
  can 
  at 
  least 
  be 
  identified, 
  although 
  

   they 
  are 
  frequently 
  modified 
  by 
  mythological 
  concepts. 
  Mochica 
  

   specializes 
  on 
  two-color 
  painting, 
  but 
  Nazca 
  aDd 
  Tiahuanaco 
  are 
  

   polychrome. 
  In 
  the 
  Middle 
  Periods, 
  influenced 
  by 
  the 
  spread 
  of 
  

   Tiahuanaco, 
  the 
  ceramic 
  designs 
  are 
  conventionalized 
  so 
  that 
  in 
  many 
  

   cases 
  they 
  can 
  be 
  identified 
  only 
  by 
  tracing 
  them 
  back 
  to 
  their 
  orig- 
  

   inal 
  sources. 
  Middle 
  Period 
  painting 
  is 
  polychrome 
  but 
  with 
  a 
  

   limited 
  range 
  of 
  colors. 
  In 
  the 
  Late 
  Periods, 
  the 
  colors 
  are 
  even 
  more 
  

   restricted, 
  modeling 
  is 
  conventionalized, 
  and 
  designs 
  are 
  frequently 
  

   geometric. 
  Finally, 
  the 
  Inca 
  Period 
  ceramics, 
  although 
  again 
  poly- 
  

   chrome, 
  are 
  dominated 
  by 
  geometric 
  design. 
  

  

  Ceramics 
  illustrate 
  an 
  apparent 
  shift 
  from 
  individual 
  to 
  mass 
  pro- 
  

   duction. 
  At 
  least, 
  the 
  Early 
  Period 
  ceramics 
  seem 
  to 
  emphasize 
  the 
  

   individual 
  artist. 
  Although 
  for 
  purposes 
  of 
  convenience 
  the 
  vessel 
  

   shapes 
  can 
  be 
  classified 
  into 
  a 
  few 
  standard 
  categories, 
  variations 
  on 
  

   these 
  are 
  numerous. 
  By 
  the 
  Inca 
  Period, 
  shapes 
  were 
  standardized 
  

   and 
  variations 
  less 
  frequent. 
  

  

  Metallurgy. 
  — 
  The 
  Spaniards 
  discovered 
  the 
  Inca 
  metallurgists 
  utiliz- 
  

   ing 
  gold, 
  silver, 
  copper, 
  tin, 
  mercury, 
  and 
  arsenic. 
  On 
  the 
  basis 
  of 
  present 
  

   knowledge, 
  not 
  all 
  these 
  metals 
  were 
  utilized 
  in 
  the 
  pre-Inca 
  periods. 
  

   Instead, 
  a 
  sequence 
  of 
  development 
  seems 
  apparent 
  in 
  spite 
  of 
  the 
  lack 
  

   of 
  analysis 
  of 
  many 
  of 
  the 
  existing 
  specimens. 
  In 
  the 
  Chavfn 
  Periods, 
  

   gold 
  was 
  the 
  principal 
  metal 
  utilized. 
  On 
  the 
  South 
  Coast, 
  the 
  gold 
  

   was 
  hammered 
  flat 
  and 
  simple 
  ornaments 
  were 
  cut 
  out, 
  some 
  of 
  them 
  

   decorated 
  with 
  relief 
  designs. 
  On 
  the 
  North 
  Coast, 
  pressed 
  relief 
  

   design 
  was 
  common, 
  and 
  there 
  is 
  some 
  evidence 
  of 
  the 
  use 
  of 
  silver, 
  

   a 
  gold-platinum 
  mixture, 
  and 
  the 
  technique 
  of 
  soldering. 
  In 
  the 
  

   Early 
  Periods, 
  the 
  goldwork 
  was 
  more 
  complex 
  and 
  new 
  techniques 
  

   were 
  added. 
  Silver 
  was 
  utilized 
  in 
  the 
  Mochica 
  Period, 
  and 
  pure 
  cop- 
  

   per 
  objects 
  have 
  been 
  found 
  in 
  the 
  Mochica, 
  Kecuay, 
  Early 
  Tiahuan- 
  

   aco, 
  and 
  Classic 
  Tiahuanaco 
  divisions. 
  There 
  is 
  some 
  evidence 
  of 
  

   the 
  use 
  of 
  lead 
  in 
  the 
  Mochica 
  Period, 
  although 
  rarely. 
  The 
  pre- 
  

   Tiahuanaco 
  Gallinazo 
  culture, 
  the 
  first 
  of 
  the 
  Middle 
  Periods, 
  utilized 
  

   combinations 
  of 
  silver 
  and 
  copper, 
  copper 
  and 
  gold, 
  and 
  a 
  gilding 
  tech- 
  

   nique. 
  Later 
  in 
  the 
  Middle 
  Periods, 
  a 
  copper-arsenic 
  alloy 
  was 
  made 
  

   on 
  the 
  North 
  Coast, 
  and 
  a 
  silver-copper 
  combination 
  was 
  in 
  use 
  on 
  

   the 
  South 
  Coast. 
  Silvering 
  was 
  added 
  to 
  the 
  metallurgical 
  tech- 
  

   niques. 
  The 
  casting 
  of 
  copper 
  was 
  common 
  in 
  the 
  Late 
  Periods, 
  and 
  

   gold 
  was 
  frequently 
  mixed 
  with 
  silver. 
  The 
  first 
  bronze 
  appeared 
  

   toward 
  the 
  end 
  of 
  the 
  Late 
  Periods, 
  and 
  perhaps 
  not 
  until 
  the 
  Inca 
  

   Period. 
  Since 
  tin 
  is 
  most 
  abundant 
  in 
  Highland 
  Bolivia, 
  presum- 
  

   ably 
  the 
  copper-tin 
  alloy 
  originated 
  there, 
  but 
  there 
  is 
  as 
  yet 
  no 
  clear 
  

  

  