remnant vs sluice box

remnant

noun
  • An unsold end of piece goods, as cloth, ribbons, carpets, etc. 

  • The remaining fabric at the end of the bolt. 

  • The small portion remaining of a larger thing or group. 

sluice box

noun
  • A box with riffles along the bottom, used to trap heavier gold particles as water washes them and the other material along the box. 

How often have the words remnant and sluice box occurred in a corpus of books? (source: Google Ngram Viewer )