Cone 6: Mirror Black creates a highly reflective, metallic black gloss finish. On some vertical surfaces and around surface textures, minor matte effects can be seen; all other applications result in the formation of a black, metallic mirror. Cone 10: Finish flattens. Color remains. Increased movement. TIP: This glaze WILL move. Take care when using on vertical pieces – reduce glaze thickness towards the bottom third to minimize run-off.