How are Aggregates Classified?

Without question, concrete is the most popular building material in the world. Almost anyone on the street could tell you as much without hesitation. Of course, the average person likely also believes that concrete is concrete and that’s that. Construction professionals, on the other hand, can tell you that concrete is about as diverse as they come. With variables such as size, shape, and consistency, there is so much more to concrete than meets the eye.

Thanks to a little help from different aggregates, concrete is one of the most adaptable materials ever created.

What Is an Aggregate?

Put simply, an aggregate is one of the various components that come together to make up a compound material, such as concrete. Typically, aggregates are sand, gravel, and crushed stone. Some of the most fascinating aspects of these seemingly simple materials are the different sizes and shapes that can be combined to form a variety of concrete types.

Different Means of Classifying Aggregates

Aggregates can be sorted on any number of levels — tactility, size, shape, weight, color, etc.


Size is one of the most important parts of classifying an aggregate. Typically, the size of the aggregate is divided between fine and coarse selections. Fine aggregate like sand is used to fill in the void created when coarse aggregates are combined. Fine aggregate is also used to fill in sand traps on golf courses.


Determining the shape of an aggregate can be particularly challenging as most aggregates are obtained by blasting or crushing. That being said, sorting aggregate by shape is always necessary as the aggregate shape will impact the concrete’s viability. Shape can be determined by the parent rock being used or the machine used to break it down.


Some builders or customers require materials that are smooth to the touch. Sorting aggregates by tactility can help achieve that goal as it sorts the material by the way it feels. Tactility is an especially important consideration in the construction of specific projects like highways or bridges.


Construction professionals easily understand the importance of properly classifying aggregates by color. Thanks to the wide ranging color spectrum of aggregates, when properly sorted, they can lend their color to concrete products of every form.

Why Proper Sorting and Classification Is Important

The integrity of your product starts with its materials. As a team with decades of experience, General Kinematics understands that the proper classification of aggregates can sometimes mean the difference between success and catastrophe. Your process needs to be able to rely on your materials without question. That’s why General Kinematics’ state-of-the-art sorting equipment is one of the most trusted brands in the field.

Seeing is believing: Let us show you proof. Send your materials to our state-of-the-art testing facility or stop by the GK booth at one of our several upcoming conferences  to learn more about the processing solutions we have to solve your toughest challenges!

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