Sandstone (sometimes known as arenite) is a clastic sedimentary rock composed mainly of sand-sized minerals or rock grains.
Doing some research you will discover most sandstone is composed of quartz or feldspar. These minerals are one of the most common found in the earth's crust. There are common colors to sandstone and we will be focusing on this for the cache. Colors can consist of tan, brown, yellow, red, grey, pink, white, and black. In the area you stand there is no cliffs or topographical features that can reveal the significance of where seneca sandstone comes from it is demonstrated on how it is used. Directing the geology of the stone will provide the information needed.
The rock formations of sandstone often come from areas where water is present. Sandstone allows aquifers to form bodies of water and easy flow. The Seneca sandstone is mostly harvested from the local area. It was common near bodies of water local to the are and is referenced later.
To quote the scientific standard: Quartz-bearing sandstone is converted into quartzite through heating and pressure usually related to tectonic compression within orogenic belts.
Sandstones are clastic from the origin it comes from. It is formed by cemented grains of rock fragments, mono-minerallic crystals. The additional minerals that binds the cementing together is usually calcite, clays and silica. The grains all vary in size but according to studies it can range .0625 mm to 2 mm in size. Grains can be smaller from sediment but are not visible to the naked eye. These are called siltstones and shales, are typically called argillaceous sediments. The visible sizes are called breccias and conglomerates are termed rudaceous sediments.
One of the most notable sandstone attractions is the red sandstone interior of Lower Antelope Canyon, Arizona. The sandstone there formed by years of erosion by flash flood which made it smooth similar to the stone where you stand.
A little bit of Maryland History:
Maryland has a significance of Sandstone used in historic structures. Much like the structure you are near it was used for its durability and easy formation into need shapes to create realiable structures that could house early founders and migrants. Much of the local sandstone known as Seneca Sandstone can still be observed in most historic structures throughout the local area.
The 1897 Geological Survey of Maryland confirmed that the most extensive quarries of the sand stone from the Triassic belt were located near the Potomac, near the mouth of Seneca Creek. This survey also made mention of several smaller quarries located further north that were used for local purposes. Here again, the attributes of the stone were given as its great strength, durability, ease with which it was able to be worked, and its beautiful colors. It was described as "one the best Triassic sandstones" (Maryland Geological Survey 1897, 212). A good example of the stones durability and value is the structure near where you stand. It is still standing to this day.
In order to claim this cache answer the questions below and send an email to the cache owner for confirmation. If you wish but not required take a picture with the structure for fun.
What is the texture of the stone, does it feel durable as noted by the history?
What is color or shade of the stone you observe?
What type of modern aging do you observe the stone has succumbed to?
Do you observe any additional minerals in any of the stone?
Bonus (Not required): For the little ones or you, locate the engraved initials on one of the stones. (Hint: near the back!)
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