• BOLE: clay laid down in a thin layer between the gesso and the gilding material on a frame molding. The color of this clay is often a clue to the origin of the frame. Red bole is characteristic of European frames, while blue/grey bole suggests a pre-1900 American provenance.

  • COMPO: composition material made of chalk and resins, used to make molded ornament.

  • COVE: concave shape. A coved molding has a concave shape, and that concave part of the profile is called the cove.

  • GESSO: mixture of glue and chalk, applied to the surface of the wooden frame structure to provide a smooth surface for the gilding material.

  • GILDED OAK: gold leaf laid directly on oak wood molding, with no intervening gesso and bole, allowing the grain of the wood to show through. Gilded oak was championed by Charles Eastlake, and it was popular during the Arts and Crafts Period.

  • OGEE: S-curve. An ogee molding has an S-shaped profile, which slopes inward toward the center of the frame. A reverse-ogee molding slopes outward toward the outside edge of the frame.

  • PROFILE: the shape of the molding when viewed on end.

  • RABBET SIZE: The L-shaped space in the back of the frame that holds the glass or the painting is the rabbet. The rabbet size defines the dimensions of that space.

  • SIGHT SIZE: The sight size defines the dimensions of the space enclosed by the frame, when viewing it from the front. The innermost molding on a composite frame is called the sight molding.

  • SILVER GILT: silver leaf coated with an orange or honey-colored lacquer. Silver gilt frames can be distinguished from their gold-leaf cousins by the small black spots on their surface, where the lacquer has worn away, exposing the underlying silver to the air and allowing it to tarnish.

    • SIMPLE MITER JOINT: molding sticks cut at 45 degree angles, and held together with glue and nails. (Figure 7)
    • SPLINE JOINT: molding ends held together by a strip of wood laid perpendicularly to the miter joint. (Figures 8+11)
    • LAP JOINT: adjoining ends of molding sticks cut with overlapping sections.
      (Figure 9)
    • MORTISE AND TENON JOINT: projecting piece (tenon) from one molding stick fits into carved out space (mortise) in adjoining molding stick.
      (Figure 10)
    • BUTT JOINT: adjoining ends of molding abutted end to side, usually with a narrow mitered surround that holds them together and makes the outside edge uniform.

Illustrations courtesy of William Adair, The Frame in America, 1700-1900. p. 9.