Translucent concrete (light-transmitting concrete) is a concrete based building material filled with optical fibers that run from one end of a poured piece of concrete to the other.

Effectively transmitting light due to fibers running through prefabricated blocks and panels, concrete is given a new look without sacrificing its strength and durability. The fibers can transmit light to over 50 feet and, as they occupy only a small percentage of the total concrete block or panel, they do not significantly affect the structural capabilities of the poured pieces. This results into a certain light pattern on the other surface, depending on the fiber structure. Shadows cast onto one side appear as silhouettes through the material. The fibers can also be used to create lettering, pictograms and "light patterns" in the concrete. Colors and light remain remarkably consistent from end to end, but with a natural variation from the pouring process that actually softens the effects considerably.

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