Bronze Materials

Silicon Bronze:

Predominantly, fasteners are made from C651 silicon bronze alloy - 97% copper, 3% silicon.

The addition of silicon to the copper results in a stronger and harder alloy, to the equivalent of mild steel.  Further adding to their strength, they are manufactured from hard drawn wire, resulting in stronger elemental bonding and alignment.

Silicon bronze has a deep rich rose gold patina when the fastener is new or polished.  If allowed to age, it will developed a red hued brown tone, akin to Florentine Bronze, and is the recommended option for fastening antique brass hardware.  One advantage of a solid silicon bronze fastener over a Florentine bronze coated fastener is the colour will never degrade over time.

As a lead free product, it is safe for use in plumbing and potable water applications.

It is an antimicrobial alloy, making it ideal to fasten high touch high risk hardware and fittings, reducing the risk of residual bacterial contamination in screw drives and threads that cannot be thoroughly cleaned.


A small number of products - primarily the rod, plate, bar and a small range of the bolts, are made from alloy C655. 


Corrosion Resistance:

Silicon bronze is the superior corrosion resistant material for salt water/marine applications and for building within 5kms of the coast.  

Unlike stainless steel based alloys, silicon bronze does not require an oxide film (access to oxygen) to maintain corrosion resistance, which makes it less susceptible to pitting and crevice corrosion. 

When a stainless steel fastener is fitted, the surface that is no longer in contact with oxygen, will lose its protective film over time.  How long that takes depends on the alloy itself, and the thickness of the film and where the fastener has been installed.  Once the coating fails, the fastener will begin to corrode.  This results in several things:
- a weak point in the fastener, which when combined with the natural work hardening that occurs on installation, makes it more prone to failure (breakage)
- unsightly oxide corrosion staining


Phosphor Bronze:

Coming soon


Copper 5 - Cu Ni Si - Kuprodur

Kuprodur is a copper, nickel, silicon high strength bronze alloy with 98% copper .

It is not susceptible to stress corrosion and very resistant to many acids, alkalis, sea water and atmospheric influences, comparable with pure copper. Kuprodur therefore is very often applied in nuclear power plants, and in the water treatment, shipbuilding, low temperature technics, electro-technical and chemical equipment industries.

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