[1] : The Collaborative International Dictionary of English v.0.48

chrome \chrome\, n.
   same as chromium.
   1913 webster

   chrome alum chem., a dark violet substance,
      so43cr2.k2so4.24h2o, analogous to, and crystallizing
      like, common alum. it is regarded as a double sulphate of
      chromium and potassium.

   chrome green
   a the green oxide of chromium, cr2o3, used in enamel
       painting, and glass staining.
   b a pigment made by mixing chrome yellow with prussian
       blue.

   chrome red, a beautiful red pigment originally prepared
      from the basic chromate of lead, but now made from red
      oxide of lead.

   chrome yellow, a brilliant yellow pigment, pbcro4, used
      by painters.
      1913 webster
see also:
chromium chrome alum so43cr2.k2so4.24h2o chrome green cr2o3 chrome red 
chrome yellow pbcro4 

[2] : WordNet (r) 2.0

chrome alum
     n : a violet-colored salt used in hide tanning and as a mordant
         in dyeing

Alum >> A Words
Alum, definition of term: Alum
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