Possible Clues:

• Printmaking technique which creates the opposite effect to a relief print
• Giant oil spills making a sort of design
• Giant oil reproduced in engraving
• Ligation (anag.)
• Engraved design — I go Latin (anag)
• Toiling away at first developing engraved design
• Cameo's inverse
• Engraving of lion -- it shimmers, silver coated
• The art or process of incised carving
• With which to make an incisive design statement