It is still #EnigMarch and I am once again responding to a dare to create a puzzle.

The jeweler knows that an uncut gem doesn't look right; you need to chip away a bit to see the precious stone. Once the jeweler is done with this batch, what color are the removed bits?

EPIGRAPHS
POLAR
BUYER
REPEAL
ALDERMEN

ROT13'd explanation and answer:

Rnpu jbeq vf gur anzr bs n trz cyhf bar yrggre, nantenzzrq. Lbh jnag gb svaq gur rkgen yrggref:

  
  RCVTENCUF : FNCCUVER + T
  CBYNE     : BCNY     + E
  OHLRE     : OHLRE    + R
  ERCRNY    : CRNEY    + R
  NYQREZRA  : RZRENYQ  + A

Gur rkgen yrggref fcryy gur nafjre, TERRA.