Opus Incertum is derived from an ancient Roman construction technique; using irregular shaped and random placed uncut stones inserted into a core of Opus caementicium (Roman cement).

Courtesy of Dagmar Friedrich, mosaic collaborator.

Opus Incertum is derived from an ancient Roman construction technique; using irregular shaped and random placed uncut stones inserted into a core of Opus caementicium (Roman cement).

Courtesy of Dagmar Friedrich, mosaic collaborator.

Opus Incertum is derived from an ancient Roman construction technique; using irregular shaped and random placed uncut stones inserted into a core of Opus caementicium (Roman cement).

Courtesy of Dagmar Friedrich, mosaic collaborator.

Opus Musivum is rather like ripples on a pond, with repeated rows of tesserae which spread out as a visual rhythm to fill a background to the edges of the mosaic area.

Courtesy of Dagmar Friedrich, mosaic collaborator.

Opus Regulatum, as the name suggests, is a very regular pattern of tesserae, like bricks in a wall, or squares on a chess board. With a subtle variation Opus Tessellatum describes rows of tesserae laid in regular horizontal or vertical lines, more generally referred when used in backgrounds.

Courtesy of Dagmar Friedrich, mosaic collaborator.

Opus Vermiculatum, refers to a single row or multiple rows of tesserae following the outline of a feature (such as a figure or other subject) in a mosaic, highlighting the subject and providing contrast against a background with tesserae laid in a different style.

Courtesy of Dagmar Friedrich, mosaic collaborator.

Opus, a creative piece of work in any field of the arts. In architecture, (from studies on the Romans) it refers to a technique, method or style of connecting building elements. Here in the sense of “artwork” the terms are used  as a way of describing the andamento, or flow of tesserae, or other features of mosaics, classifying the different styles of placement and juxtaposition.

Opus Vermiculatum, refers to a single row or multiple rows of tesserae following the outline of a feature (such as a figure or other subject) in a mosaic, highlighting the subject and providing contrast against a background with tesserae laid in a different style.

Opus Regulatum, as the name suggests, is a very regular pattern of tesserae, like bricks in a wall, or squares on a chess board. With a subtle variation Opus Tessellatum describes rows of tesserae laid in regular horizontal or vertical lines, more generally referred when used in backgrounds.

Opus Regulatum, as the name suggests, is a very regular pattern of tesserae, like bricks in a wall, or squares on a chess board. With a subtle variation Opus Tessellatum describes rows of tesserae laid in regular horizontal or vertical lines, more generally referred when used in backgrounds.

Opus Musivum is rather like ripples on a pond, with repeated rows of tesserae which spread out as a visual rhythm to fill a background to the edges of the mosaic area.