cast bronze plaques
Cast bronze is the material of choice when permanence, prestige, and visual richness are non-negotiable. Used in memorials, government buildings, universities, and landmarks worldwide — bronze outlasts every other option and only grows more beautiful with age.
Architectural Grade Alloy
C83600 · ASTM B584
The Alloy
What Is C83600 Architectural Bronze?
The high copper content (85%) gives fresh bronze its characteristic warm amber-red color, and is responsible for the self-healing patina system that develops over years of outdoor exposure. The tin content adds hardness and improves casting quality, while the lead and zinc components aid flow properties during the pour.
Alloy Composition by Weight
The Aging Process
How Bronze Ages Beautifully
Unlike materials that fade or degrade, bronze develops a protective patina that actually seals and preserves the metal underneath — growing more beautiful over time.
Fresh Cast
Freshly cast and finished bronze has a warm amber-gold color — closer to copper than what most people picture as "bronze."
1–3 Years
Outdoor oxidation deepens the surface to rich warm browns. The metal begins developing a thin protective oxide layer.
5–15 Years
The patina deepens to rich dark umber and chocolate tones. The oxide layer is now substantial and actively protecting the metal.
20–50 Years
In humid environments, green verdigris begins to appear — particularly in recesses and corners. Widely considered the mark of true age and prestige.
50–100+ Years
The full green-grey patina of historic bronze — the Statue of Liberty is an example. The plaque is now fully self- sealed and effectively immortal.
Full Specifications
Technical Data
Property
Value
Alloy Designation
C83600 (ASTM B584)
Composition
85% Cu · 5% Sn · 5% Pb · 5% Zn
Casting Method
Sand casting, chemically-bonded mold
Pour Temperature
1,850°F (1,010°C)
Tensile Strength
37,000 psi
Density
0.318 lb/in³ (~8.8 g/cm³)
Standard Thickness
3/8 inch base field
Relief Height
Up to 3/4 inch (title letters)
Background Color
Hunter Green (RAL 6009), baked enamel
Clearcoat System
Marine-grade polyurethane, 25-yr rating
Mounting
Stainless 3/8″ anchor bolts (template incl.)
Outdoor Lifespan
100+ years documented
Warranty
Lifetime — full replacement
Why Choose Bronze
Seven Reasons Bronze Wins
Unmatched Longevity
Every plaque is hand-reviewed before shipment. We accept nothing less than perfection.
Self-Sealing Patina
The patina that forms is a protective copper carbonate layer that actually hardens and seals the metal beneath it over time.
Visual Depth
The weight, warmth, and three-dimensional richness of cast bronze is instantly recognizable and cannot be replicated by cheaper alternatives.
Institutional Prestige
Bronze signals permanence, investment, and seriousness. It communicates that the person or institution being honored deserves a lasting tribute.
Coastal Durability
Outperforms aluminum in salt-air environments. The copper alloy resists chloride corrosion that can pit and degrade aluminum alloys over time.
Intrinsic Value
Bronze contains real copper — a commodity metal with lasting value. Your investment holds material worth beyond just its commemorative function.
Vandalism Resistant
The density and hardness of cast bronze makes it extremely difficult to deface — far more resistant to graffiti and physical damage than softer materials.