A set of four boulder opals with interesting patterning.

• 17.49 carats (total).
• Left, 22.4 x 8.4 mm / 0.88" x 0.33".
• 3.5 mm / 0.13" thick.
• Middle left, 20.3 x 7.5 mm / 0.79" x 0.29".
• 3.7 mm / 0.14" thick.
• Right middle, 15 x 13.6 mm / 0.59" x 0.53".
• 3.6 mm / 0.14" thick.
• Right, 17 x 6.9 mm / 0.67" x 0.27".
• 3.1 mm / 0.12" thick.
• Natural solid boulder opals.
  
• Mined by Sue at her Yaraka opal mine in Queensland, Australia.
• Lower commercial grade.