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Dwarves' Earth Treasures Museum: How to ID Agate Roughs
  Aqua Nueva Agates

 

Typical colors: Gray, white, pink, red, and colorless
Typical sizes: Large (10 centimeters or larger)
Typical shape: Potato-like.
Most distingishing characteristic: Large "Laguna-like" nodules commonly with moss/plume/feather characteristics with thick colorless layers between colored layers.