Possible Clues:

• The colour is right in the line of fire for darts
• Yellow / red pigment
• Personnel get soaked by flipping green paint
• A shade hot? On going under zero, cold!
• Northerner's expression of surprise about pigment
• Pigment only cool-headed restorers employed originally
• So dramatic, with lunar eclipse, finally to see earth's shade
• Northerner's cry of surprise about pigment
• Pigment with touch of red in ridge
• Pigment found in the Dornoch region