Decorative Materials FAQs

Cold-cast bronze commonly means bronze powder combined with resin and formed in a mould. Smooth-On describes a process that can use a metal-filled surface layer with a different backing. This differs from pouring molten bronze in a foundry. Ask which material forms the body as well as the surface. The term alone does not tell you the proportions or construction of a particular ornament.

Further reading: Smooth-On: Bronze Metal Powder.

Yes. Bronze sculptures can be cast as metal shells around an internal core rather than as completely solid masses. Getty explains that hollow casting reduces the amount of metal and can help limit casting problems. A hollow interior therefore does not by itself establish that an object is an imitation. When comparing ornaments, ask separately about the alloy, construction, dimensions and weight instead of treating weight alone as proof.

Further reading: Getty: Guidelines for the Technical Examination of Bronze Sculpture.

Pewter is a tin-based alloy, not a type of silver. Other metals are added to change its working properties, and recipes have varied over time. The Pewter Society describes historical mixtures as well as later tin, antimony and copper alloys. When reading about an older piece, keep its date and stated composition together. Do not use the name pewter alone to infer the exact recipe of an unidentified object.

Further reading: Pewter Society: The Metal.

Polymer clay is a synthetic modelling material with a plastic polymer base. Sculpey identifies that base as PVC, with other ingredients affecting softness, colour and texture. It should not be described as pottery clay simply because both can be shaped. For an ornament or jewellery component, keep the exact material term in the description rather than assuming a smooth finish means porcelain.

Further reading: Sculpey: Common Polymer Clay Questions.

No. MDF means medium density fibreboard, an engineered board made by bonding wood fibres with a resin adhesive. It is not a piece cut directly from solid timber. The European Panel Federation explains that MDF can receive paint, decorative foils or wood veneers. Read the body material and surface finish separately when comparing decorations; a wood-like surface does not establish that the underlying object is solid wood.

Further reading: European Panel Federation: Medium density fibreboard.

The number expresses silver content in parts per thousand: 925 corresponds to 92.5% silver. It describes the fineness of a silver alloy, not an item that is entirely pure silver. Read the complete product wording and ask which component it describes, especially for pieces with several materials. A number in a listing is not, by itself, an independent identification of the object you are buying.

Further reading: Birmingham Assay Office: How to Read a UK Hallmark.

They use related electrical techniques for different purposes. In the V&A’s electroforming example, metal builds up against a conductive mould, which is then removed to leave the metal form. Electroplating puts a metal coating onto an already formed object. A piece can be both electroformed and plated. If a listing names only one process, ask what metal was formed and what, if anything, coats it.

Further reading: V&A: A guide to metalworking techniques.

Vitreous enamelling uses glass fused onto a metal support to create a decorative surface. The enamel is therefore a separate material from the metal beneath it. GIA describes several ways of arranging that glass, including filling small metal compartments in cloisonné work. If a description says only enamel, ask about the technique and underlying metal rather than trying to identify the whole object from its colour.

Further reading: GIA: The Art of Enameling: The Techniques.

Porcelain is a type of ceramic, alongside earthenware and stoneware. For these clay-based objects, ceramic is the broader category; differences between the types involve the mixture used and its firing. Dutch Delftware describes earthenware as having a porous body and stoneware as having a hard, non-porous body. A listing that says only ceramic leaves the more specific material unstated, so ask for it when comparing pieces.

Further reading: Dutch Delftware: Types of ceramic.

The body is the clay-based substance forming the object. Glazing is one kind of surface treatment, while decoration describes features such as patterns, colours and applied designs. Florida Museum treats these as separate attributes when identifying historic ceramics. A similar painted design can appear on different ceramic bodies, so record the material and finish separately. An attractive pattern alone cannot tell you which ceramic type lies underneath.

Further reading: Florida Museum: Introduction to Ceramic Identification.