Bronze Plaques vs. Aluminum Plaques: Which is the best material for your cast metal plaque?

examples of bonze and aluminum plaques including a large legacy memorial plaque, community dedication plaque and building and house plaques

Creating a high-quality, legacy signage project may find you weighing the options of choosing between a bronze or an aluminum plaque. Which material is best for your family or community project? Or are you looking for a personalized plaque to display at your business, school, or home? Cast bronze and aluminum plaques are two of the most popular materials used in creating indoor and outdoor memorials and other types of high-quality signage. While both materials are durable and long-lasting, there are significant differences between the two that make each one more suitable for certain applications.

Custom Bronze Plaques - Luxurious and Long Lasting

outdoor cast bronze plaque for golf club

What are bronze plaques made of?

Bronze plaques are typically made with a metal alloy of copper and tin. This gives them a distinctive reddish-brown color. The use of different alloys of copper has an effect on the final color. Some of the most common alloys for cast bronze plaques are Red Brass or Silicone Bronze which both have greater than an 85% copper content.

How is a bronze plaque made?

Cast bronze plaques are made by using a sand molding method, which involves creating a sand mold of the desired design from a pattern and then using that to cast the plaque in bronze. This process produces a highly detailed and precise finished product.

What are bronze plaques typically used for?

A bronze plaque is often chosen to commemorate loved ones, to honor a hero, in dedications for service, or in memorials. This is due to their classic look and durability. Bronze plaques are a top choice as a memorial plaque on a park bench along pathways, in community parks, in memorial gardens at churches, and in other commonplaces. Dedications made of bronze are often found outside of community buildings in city centers and downtown areas.

Benefits of Bronze Plaques

bronze plaque for historical home founded in 1766


One of the main benefits of bronze plaques is their ability to withstand harsh weather conditions and resist corrosion. Bronze is a highly durable material that can last for centuries, making it an ideal option for outdoor plaques that need to withstand exposure to the elements. If you are looking to install a sign on the ground, your best bet is to go with a custom bronze plaque that has a hardness that withstands more wear and tear.

Timeless Luster

Additionally, a bronze plaque has a timeless and elegant appearance that many people find appealing. The sheen from the finished raised letters and borders on a bronze plaque is quite remarkable. This is why it is a chosen material for many memorial plaques. The admirable aesthetic of a bronze memorial plaque brings solace to those who view it on display in remembrance of a loved one or esteemed figure in the community.

Refinishing Capabilities

Bronze memorial plaques that are hundreds of years old can be polished and finished with a protective coating to last hundreds more. Bronze plaques are the highest quality material for a memorial plaque and create an eternal memorial for future generations to enjoy.

Aluminum Plaques - Affordable and Versatile

detail of a cast aluminum house plaque with house number and street name

What are aluminum plaques made of?

The higher quality aluminum plaques are made of 535 Aluminum (Almag) which is an aluminum alloy consisting of mostly aluminum with a 0.15% silicon, 0.003 to 0.007% beryllium, 0.5% iron, 0.15% copper, 6.5 to 7.5% magnesium, 0.25% titanium, 0.15% zinc, 0.35% manganese, and less than 0.005% boron. This type of aluminum provides the best corrosion resistance.

Another type of aluminum alloy used in casting is 356 Aluminum (Standard), made up of 92.05% aluminum, 7% silicon, 0.35% magnesium, 0.20% iron, 0.20% copper, 0.10% manganese, and 0.10% zinc. The A356 alloy also provides excellent corrosion resistance, as well as very good machining & weld-ability characteristics, and excellent mechanical properties.

How are custom aluminum plaques made?

Similar to making a bronze plaque, aluminum plaques are typically made using the same sand casting process. Sand casting involves pouring molten aluminum into sand molds to create the desired shape. Once the metal cools, it goes through a cleanup, polishing, and finishing process to create a final, high-quality custom cast aluminum plaque.

What are aluminum plaques typically used for?

Aluminum is a lightweight and versatile material that is often used for plaques that need to be mounted on walls, and other indoor surfaces, or mounted on posts for outdoor directional signage. Aluminum plaques can be painted or powder-coated to achieve a wide range of colors, making them highly customizable. Cast aluminum wall plaques are great for company signage such as at the door of suites inside buildings. The color options help to better match company branding.

House number plaques made of aluminum can be a great addition for curb appeal if you want to match the colors of a more modern, craftsman-type home. Cast aluminum is also commonly found at golf courses for directional signage.

Benefits of Aluminum Plaques

aluminum plaque for art installation with description in small detailed cast text


One of the main benefits of choosing cast aluminum plaques is affordability. Because aluminum is a less expensive material than solid cast bronze, it is often a more cost-effective option for larger plaques or for anyone on a budget.


Cast aluminum plaques are lightweight and easy to install, making them a popular choice for indoor applications. Being lightweight, they offer flexible mounting options. They also cost less to ship because aluminum plaques weigh significantly less than bronze plaques.

Indoors or Out

The alloy of aluminum is an important factor in determining corrosion resistance when placed in outdoor applications. So choosing the right alloy for outdoor applications will ensure better longevity. The oxidation effect on aluminum is not as desirable compared to the superior cast bronze plaque material.

Yet while bronze is the preferred material for outdoor signage, when properly coated, finished, and maintained, aluminum is a very popular and viable outdoor signage option. The metal itself will last a decade or more, but once the coatings are compromised they will most likely oxidize quickly and leave a white chalky residue that is tough to clean off. At Signature Streetscapes, we warranty our coatings on aluminum for 1 year, but based on our experience you can expect 4-8 years of exceptional performance--even in harsh conditions.

Finer Detail in Design

The aluminum alloy also allows for more detail in your plaque design. Text can be cast at a smaller size, adding more information on personalized plaques that have a story to tell. For cast metal plaques that require a lot of text, the overall plaque size could be smaller on aluminum than it would for the same text cast bronze plaques.

Bronze Plaques vs. Aluminum Plaques - Pros & Cons

Here is a list to break down the pros and cons of aluminum vs bronze plaques for you to easily consider:

Pros of Buying a Cast Bronze Plaque:

  1. Longer lasting
  2. Durable
  3. Elegant natural color
  4. Able to be refinished

Cons of Bronze Plaques:

  1. Heavier, more difficult to install
  2. More expensive
  3. Less detail in small bronze letters

    Pros of Buying a Cast Aluminum Plaque:

    1. More affordable - lower cost
    2. Lightweight, flexible mounting methods
    3. Allows for more detail in design
    4. More color options for raised areas

      Cons of Aluminum Plaques:

      1. Softer and easier to get damaged
      2. Oxidizes quicker (if not properly sealed)
      3. Not able to be refinished after longtime wear

        In conclusion, both cast bronze plaques and cast aluminum plaques have their own unique benefits and are suitable for different applications. Custom bronze plaques are ideal for outdoor memorials and commemorative plaques due to their durable nature and timeless appearance, while aluminum plaques are more versatile and affordable, making them a popular choice for indoor applications. Ultimately, the choice between a bronze plaque or an aluminum plaque will depend on your specific needs and budget.

        More information about buying a custom plaque

        If you are thinking about purchasing personalized cast plaques you will find many helpful tips on our website. We also have a one-page cast plaque maintenance guide to help you better understand what maintenance and refinishing options you can expect.

        About Tim Mills

        photo of author, Tim Mills, owner of Signature Streetscapes

        Tim has worked in the sign fabrication and metal casting industry for over 25 years. Owner and founder of Port City Architectural in 2006, the company has grown and expanded into new markets since its humble beginnings. Tim holds a Bachelor of Management and Marketing from Grand Valley State University.