Materials
Materials, silicon bronze and brass
Silicon bronze and brass. Both are copper based and both reach a similar range of finished colours once the patina is on, which is why buyers so often cannot tell them apart by eye. Bronze costs more in metal and suits work meant to last and be resold. Brass costs less and suits decorative and cost led work. We will not describe a brass casting as bronze.
01 · What we cast
What we cast
Sculpture and decorative work in copper based metals, using lost wax casting. Two metals cover almost everything we make:
- Silicon bronze, for work meant to last and be resold
- Brass, for decorative work and cost led projects
Both reach a similar range of finished colours once the patina is on, which is precisely why so many buyers cannot tell them apart. The difference is in the metal, the price and what the piece will be worth in ten years. If you are choosing between them, start with silicon bronze compared with brass.
Scale runs from jewellery size upward. The crucible holds 500 kg.
The largest work to leave the foundry, and why size is rarely the real constraint, is covered on services and about.
02 · Two metals
Two metals
Deco casts in two copper based metals.
| Silicon bronze | Brass | |
|---|---|---|
| Base | Copper, alloyed with silicon | Copper, alloyed with zinc |
| Finished colour range | Broad, warm through dark through verdigris | Broad, and overlapping heavily with bronze once patinated |
| Relative material cost | Higher | Lower |
| Typical use here | Editioned sculpture, commissioned pieces, work meant to last and to be resold | Decorative work, higher volume runs, cost led projects |
The honest summary: when budget leads, brass. When the piece has to last and hold its value, silicon bronze. They are both legitimate choices. What is not legitimate is charging for one and delivering the other.
03 · Why buyers confuse them
Why buyers confuse them
Because after patina they can look the same.
Patina is a chemical reaction on the surface of the metal, and both alloys accept a similar range of colours. Stand a patinated brass next to a patinated silicon bronze under the same light and most buyers, including experienced ones, cannot separate them by eye. Weight will not settle it either. Neither will a photograph.
That is the whole reason this site has a page called is this bronze or brass, and how would I know. The answer is not "look harder". The answer is that visual inspection is the wrong tool, and the right tool is paperwork.
04 · Common mistake
The part buyers most often get wrong
A finished bronze and a finished brass can look identical side by side. Buyers routinely bring us a brass piece and call it bronze, or ask for bronze at a brass price, or return from a cheaper quote elsewhere believing they were offered the same thing.
They usually were not. They were offered a different metal.
We will not label brass as bronze, even when a client asks us to. That is not a criticism of anyone else in the trade. It is simply the standard we hold, and the reason the bronze or brass page exists: so a buyer can verify what they are being sold, from anyone, before money moves.
05 · What to ask for
What to ask any foundry for
Not just us. Any of them.
- The metal named on the quotation and on the invoice. Not "bronze finish", not "bronze colour", not "bronze effect". The metal.
- Whether the piece is solid cast metal or a resin composite. Cold cast and bronze resin are a different product entirely. See is cold cast bronze real bronze.
- What the patina is. A chemical patina on the metal, or a painted finish imitating one.
- What happens to the mould when the edition closes, if the work is editioned. See who owns the mould.
A foundry that answers all four plainly and in writing is telling you what you are buying. That is the entire test, and it costs nothing to apply.
06 · What we do not publish
What we do not publish
We do not publish alloy compositions, pour temperatures or ceramic shell formulations. Those are the specifics of how the shop runs, and no buyer needs them in order to know what they are purchasing. What a buyer needs is the metal named on the document, and that is always there.
07 · Choosing between them
Choosing between them
If the piece is an edition, will be resold, or is meant to be a permanent work, silicon bronze. If the piece is decorative, cost led, or part of a larger run where the budget is the constraint, brass is a real and reasonable answer rather than a compromise.
The longer version, with the decision laid out, is on silicon bronze or brass, which should I cast in.
08 · Common questions
Common questions
What is the difference between bronze and brass?
Both are copper alloys. Bronze is copper alloyed principally with tin or, in the case of silicon bronze, with silicon. Brass is copper alloyed with zinc. They cast differently, they cost differently, and they are not interchangeable, even though a finished patina can make them look the same.
Can I tell bronze from brass by looking at it?
Usually not, once a patina is applied. Raw brass tends to look yellower and raw bronze warmer or browner, but patina removes that clue entirely. This is exactly why the metal should be named in writing on the quotation.
Which metal is more expensive?
Silicon bronze. The gap is in the raw metal, and it is large enough that a quote well below the market for a bronze piece is worth a second question about which metal is actually being supplied.
Do you publish your alloy composition?
No. We name the metal, silicon bronze or brass, on the quotation and on the invoice, which is what a buyer needs in order to know what they are getting. The exact composition is not published.
Will you label a brass piece as bronze if I ask?
No. If a project is brass, the paperwork says brass. This is not a judgement about anyone else's practice. It is the standard we hold, and it is the reason a client can rely on what our documents say.
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Get a feasibility estimate
Tell us the idea and the size. We will tell you whether it is castable, in which metal, and roughly what range it sits in.