Featured News. Greens Sand has been in the silica sand industry since 1979 and has been a distributor of specialised silica sand to the Industrial as well as Leisure market for over 30 years, distributing nationally and across borders. We store a wide range of grades of silica sands.
Standing almost due east of the Reflecting Pool and the Lincoln Memorial, the monument, made of marble, granite, and bluestone gneiss, is both the world's tallest stone structure and the world's tallest obelisk, standing 555 feet 7 11â32 inches (169.351 m) tall.t the time of its completion, it was the tallest building in the world, a title it retained until the Eiffel Tower was completed in 1889; however, the Washington Monument is still the tallest stone structure in the world.
The Washington Monument was constructed in two phases after laying the cornerstone in 1848. The color line shows where construction halted in 1856, when private donations to fund the Monument dried up. Groups in charge of raising money argued over how the monument should represent George Washington and the nation.