Why Are Gray Concrete Blocks More Common Than Colored Blocks?

When you’re shopping for concrete blocks in Middleburg, PA, the vast majority of them will probably be gray. When it comes to concrete block FAQs, “Why are concrete block usually gray?” is one of the most common questions.

The answer is simple: the cement used to make concrete blocks is gray. Unless the maker adds dyes, it’s cheaper and faster to produce gray concrete blocks. Read on to learn more about concrete blocks and why some are colored.

Why are concrete blocks gray?

Not all concrete blocks are gray, but most of them are. Concrete masonry is a popular building method: it’s durable, versatile and relatively inexpensive, making it suitable for year-round use. However, if you’re not a fan of plain gray buildings, concrete masonry probably looks boring.

The reason concrete blocks are gray is because they are primarily made of cement, and cement is gray. This is due to the iron ore content in cement. Iron ore is black, and when it’s mixed with other materials, the concrete turns gray.

You may have noticed that not all concrete is the same shade of gray, either. That’s because each manufacturer mixes its cement and concrete differently. This can account for the differences in shade—which means if you’re using concrete masonry for your next project, it’s smart to get all of your blocks from the same manufacturer.

Coloring concrete blocks

You’re not limited to gray concrete blocks, though. Manufacturers also add dyes to concrete in order to tint the blocks. While there are limits to your color options (sorry, there’s currently no way to make dayglo or neon concrete shades), it does mean that you can simulate brick or opt for prettier shades.

Iron oxide, chromium oxide and cobalt are used to create different concrete shades. Natural and synthetic iron oxides can turn gray concrete red, black or yellow, depending on the mixture. When mixed together, they can also create tan, buff, brown, orange and maroon. These natural neutrals make it possible to simulate brick or other natural tones.

If you want green concrete blocks, the concrete is tinted with chromium oxide. Chromium oxide creates the green tint, while cobalt can turn concrete different shades of blue. Of course, these can also be mixed together to achieve different concrete colors.

Should you desire black concrete blocks, your manufacturer may go a step further than iron oxide: carbon can be used to turn the concrete a deep shade of black or charcoal gray.

Why use colored concrete?

Colored concrete might be more expensive and uncommon than gray concrete blocks, but it’s primarily used for aesthetic purposes. Many designers use colored concrete blocks to create a unique design, to break up large expanses of gray concrete or to simulate other building materials.

If you’re interested in learning more about all the concrete block colors available to you in Middleburg, PA, reach out to Beavertown Block Co., Inc. We pride ourselves on offering superior masonry, whether you’d like standard gray blocks or a flashier color. For answers to more of your concrete block FAQs, call to schedule a consultation!