Black rock crushed sand, also known as black aggregate stone or manufactured sand (M-sand), is a type of fine aggregate produced by crushing hard black rocks, primarily basalt or black granite. 

Here's a breakdown of its key characteristics

1. Origin and production

• It's derived from the crushing and processing of igneous rocks like basalt or black granite.
• The crushing process takes place in quarries or specialized facilities, where larger stones are broken down into smaller, sand-sized particles.
• This contrasts with natural sand, typically sourced from riverbeds and formed by natural erosion and weathering. 

2. Appearance

• As the name suggests, it exhibits a dark coloration, ranging from deep charcoal to jet black.
• This dark hue is often attributed to the mineral composition of the source rock, such as magnetite or basalt fragments. 

3. Texture and shape

• Black rock crushed sand typically has an angular and cubical particle shape with a rough texture.
• This angularity provides better interlocking properties when mixed with other materials like cement, contributing to higher strength and durability in construction applications. 

4. Applications

• It's widely used in construction as a substitute for natural river sand, especially in areas where natural sand extraction is restricted due to environmental concerns.
• Common applications include concrete production, mortar mix, asphalt, landscaping, agriculture, manufacturing of concrete products, and various environmental applications.
• It's particularly recommended for applications requiring higher strength and durability, such as reinforced concrete structures, according to Brick & Bolt. 

5. Advantages

• Offers consistent quality and controlled particle size distribution.
• Provides higher strength and durability in concrete mixes compared to natural river sand.
• Reduces environmental impact by lessening the reliance on natural river sand extraction. 

6. Disadvantages

• Can require more water and cement to achieve the desired workability in concrete mixes compared to natural sand.
• May contain micro-fine particles that can affect concrete strength. 

In summary, black rock crushed sand provides a valuable and sustainable alternative to natural river sand in numerous construction and industrial applications, offering benefits in strength, durability, and environmental impact. 

AI responses may include mistakes. Learn more