45 Minute Fire Rating Each block is supplied with an blueberry-colored bonding coating designed to enhance adhesion of the mortar and provide the block with its distinctive color. This block does not include pre-drilled holes and is not intended for crafting purposes. Visible Light Transmission: 71% Shading Coefficient: .65 Sound Transmission S.T.C. (dB): 41 Solar Heat Gain Coefficient: .66-.68 Thermal Resistance R-Value: 1.89 Heat Transmission U-Value (BTU/hr ft2 F): .53 6x6x3 Blueberry Arctic Glass Block – Bold Color Meets Cool Elegance Bring a pop of vibrant color to your space with the 6x6x3 Blueberry Arctic Glass Block. Inspired by the rich hue of blueberries, this striking shade of blue is both refreshing and eye-catching. The subtle Arctic pattern adds a soft, frosted texture that beautifully complements the vivid color, creating a truly unique and versatile look. Whether you're pairing it with clear blocks for a subtle accent or going all-in with a bold blue statement wall, the way light reflects through this glass is simply stunning. It's the perfect way to add personality, style, and color to any project.