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Lily Dia Jewellery

What Is Electroform Gold? Electroforming Jewellery Explained

Last updated 17 October 2026

Electroform gold is a gold or gold-alloy shell made by electroforming, a process that deposits metal from a solution onto the electrically conductive surface of a model called a mandrel. Removing a suitable mandrel leaves a hollow form, allowing a large piece with less weight. Some jewellery sold as electroformed retains a core or filler, so check the stated gold fineness and what is inside. Electroforming describes the method, rather than the amount of gold in a piece.

How a hollow electroformed piece is made

The model supplies the shape, and the deposited metal becomes the shell. This is one hollow-jewellery route; the materials and finishing steps vary with the design and manufacturing system.

  • Prepare the surface. A model that does not conduct electricity, such as wax, needs a conductive layer before metal can deposit onto it.
  • Build the shell. Electric current drives metal deposition from an electrolyte onto the prepared surface until the intended shell has formed.
  • Separate and finish. A suitable mandrel is released or removed using a method chosen for its material. The shell can then be finished and assembled into jewellery.
Conceptual cross-sections of a hollow-jewellery electroforming route: a model has a conductive surface, deposited metal builds a shell around it, and removing a suitable core leaves a hollow metal shell. The shell thickness is exaggerated for clarity.
One route to a hollow metal shell. Some electroformed jewellery retains a core or filler. Cross-sections are not to scale.
Umicore’s explanation of the manufacturing stages

Gold purity and what is inside

Gold purity describes the gold-bearing metal, while hollow or filled describes the construction. These are separate questions. A large electroformed piece can contain much less gold than its size suggests, particularly when part of its weight comes from a non-metal core. Ask for the metal weight separately from the total item weight when it is available.

  • Check the description of the shell metal and any final plating, rather than judging by its gold colour.
  • Ask whether the inside is hollow or contains resin or another material.
  • For an uncertain or second-hand piece, ask a qualified jeweller about verification. GIA’s examination of a filled bracelet showed why surface analysis alone may miss the construction underneath.
GIA’s examination of an electroformed gold bracelet

What to ask about wear and care

Electroforming can give earrings and pendants a generous shape without the weight of a solid metal version. That advantage comes with design choices: the shell’s thickness and shape affect how well it resists pressure. The manufacturing label alone cannot tell you how a particular piece will stand up to wear.

  • Ask the maker whether the piece suits your intended wear, particularly if it will be knocked or squeezed.
  • Use the maker’s care instructions for the whole piece, including its finish, stones and any filler, and avoid pressure that could deform a thin shell.
  • Before resizing, polishing or repair, tell the jeweller that the piece is electroformed and ask them to assess its construction.
Chris Corti on electroformed jewellery properties and design

Frequently asked questions

Is electroformed gold real gold?
Gold electroforming can produce a shell of genuine gold or gold alloy. Ask for the stated gold fineness and a description of the whole construction, including any core, filler or separate surface coating. The word electroformed describes a manufacturing method; it does not establish the amount or purity of gold in a particular piece.
What is the difference between electroforming and electroplating?
Both use electrodeposition. Electroforming builds the metal body of a piece, often as a shell around a removable model. Decorative electroplating adds a surface coating to an existing object. An electroformed piece can also receive a separate plated finish, so the shell metal and the surface finish may differ.
Is electroformed jewellery durable?
Its resistance to damage depends on the metal, shell thickness, shape and construction. A thin hollow piece can dent under pressure, while a different design may be stronger. Ask the maker about the specific piece, especially for a ring or bangle that will receive frequent knocks.
Is all electroformed jewellery hollow?
No. Removing a suitable mandrel produces a hollow shell, but some electroformed jewellery contains wax, resin or another core material. GIA has documented an electroformed bracelet with a wax or resin interior. Ask whether the piece is hollow, filled or formed around material that remains inside.

Sources and further reading

Talk through electroforming with us

Tell us what you have in mind, even if it is only a budget and a piece of jewellery type, and we will help you weigh up the options. We reply to every enquiry, usually within one business day.

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