Geology Lesson to help you identify Granite, Marble, and Limestone Gravestones in your Cemetery.

Here is a quick Geology Lesson to help you identify gravestones in your local cemeteries.
The two most common gravestones in most cemeteries are Granite and Marble. You will also find many examples of Limestone grave markers.
Granite gravestones are very common due to their availability and low cost. Granite is an igneous rock meaning it was formed as the direct result of liquefied silicon-rich felsic material exuding from a magma chamber. Granite is plutonic which means that it cooled very deep below the surface of the earth. As this material cooled, quartz crystals formed as part of the process that created the rock.
Limestone is a sedimentary rock. Sedimentary rocks form much closer to the earth's surface than granite. Generally, limestone is composed of sea creatures such as the mollusks seen in this video. As these creatures die, they settle to the bottom of a large body of water such as a sea or an ocean. They settle and eventually lithify into limestone. When you find Limestone Grave Markers, you can often see visible signs of fossils.
Marble is a metamorphic rock. Metamorphic rock is formed when pressure and heat is applied to a different (parent) rock. This heat and pressure does not liquify the parent rock but it does change the structure of the rock. The process is called metamorphosis and it eradicates all previous evidence of fossils.
Gravestones are fascinating and by learning geology, we can learn more about gravestone composition.