This is an earthcache. There is no physical cache. To log this Earthcache, read the geology lesson and answer these four questions. .
QUESTIONS:
1. What type of rock is used in this memorial?
2. What gives this rock its red color?
3. Was this rock formed by an intrusive or extrusive process?
4. Describe the textures and color of the granite faces. If there are differences, explain why?
5. Optional: Post a photo with your log that indicates you are at the location.
This location was established in 1869 as a cemetery for Freedman's Town. In the 1930’s the cemetery was essentially destroyed by the construction of the road that became the Central Expressway. In 1965 Dallas agreed to establish this memorial.
The archway entrance and adjoining walls, planters, and benches are made from Texas Red Granite. It is a type of granite that ranges in color from pink to deep red. The stone used for this memorial leans more toward the pink. The hue comes from its feldspar mineral content.
Granite is a sturdy, hard, igneous rock. It is a medium to coarse grained rock that is made up of different minerals, mostly feldspar, quartz, and mica. In general granite comes in a range of colors, typically white, pink, black, and gray.
Igneous rocks are formed when molten rock cools and hardens. Magma is molten rock beneath the surface and lava is molten rock on the surface. The term “intrusive” means the rock coagulated beneath the surface from cooling magma. Rocks that cooled from lava on the surface are called “extrusive.” Texas Red Granite is considered to be an intrusive rock.
The mineral orthoclase is most widely known as the pink feldspar found in granites. The pinker or redder the color of the stone, the larger the amount of feldspar is in the granite. The light colored crystals in granite are quartz, and the dark crystals are mica or hornblende. These crystals are mixed in the rock giving it a salt and pepper look. In fact, the name "granite" is derived from the fact that the rock appears to be composed of numerous "grains" or crystals that form a solid, durable rock.
Texas boasts two major quarries in central Texas that produce Texas Red, and each has quite a large amount. Once quarried, the granite slabs for this project were transported to Freedman Cemetery and cut on-site, as the finished pieces would have been far too large to risk moving for fear of damaging them.