Welcome to this EarthCache!
If you’re new to EarthCaching, there’s no physical container to find.
Your observations and answers are your proof of visit!
This Earthcache is here to help you learn about the different types of rocks used to make headstones. If you’ve ever walked through a cemetery, you might have noticed that some headstones look new and clear, while others are so worn down you can barely read the names or see the designs. That’s because different rocks react to weather in different ways.
To complete this Earthcache, you’ll need to go to each Waypoint and answer the questions there.
Important Reminder: Please be respectful while visiting. This is a place where people are buried, and it’s important to show kindness and care. Only visit this Earthcache during the daytime.
Mohs Hardness Scale
The Mohs scale of mineral hardness is a qualitative scale which characterizes the scratch resistance of various minerals through the ability of a harder material to scratch a softer material.
Please DO NOT scratch any of the headstones. Just touch and feel.
Scale Number - Mineral Name
- 10 Diamond
- 9 Corundum
- 8 Topaz
- 7 Quartz
- 6 Orthoclase
- 5 Apatite
- 4 Fluorite
- 3 Calcite
- 2 Gypsum
- 1 Talc
Sandstone
Sandstone is a sedimentary rock, which means it forms from layers of sand and other materials that build up over time. These layers are often found on beaches, in sand dunes, or along river valleys. Sandstone is made of fairly large grains that you can see easily, and it feels gritty like sandpaper.
The main minerals in sandstone are quartz, feldspar, and muscovite. The grains are held together by a natural “cement,” and depending on what that cement is made of, sandstone can wear away (erode) more or less easily. Quartz grains are tough and don’t break down easily, but the whole rock can still be affected by weathering from wind, water, and chemicals.
On the Mohs hardness scale, sandstone scores between 6 and 7.
Look at the PRESCOTT headstone.
- How does the stone feel?
- Do you notice any weathering?
Marble
Marble is a metamorphic rock, which means it was changed by heat and pressure deep inside the Earth. It starts out as limestone, but the heat and pressure cause the minerals in the limestone—like calcite and other carbonates—to form new crystals. This process makes marble smooth and fine-grained.
Marble is usually white, but it can have other colors if there are impurities (extra materials) mixed in. Its main minerals are calcite and dolomite. Marble is harder than limestone because of the heat and pressure it went through, so it weathers more slowly. But it’s still a soft stone compared to others.
On the Mohs hardness scale, marble has a score of 3.
Look at the MILLER headstone.
- How does the stone feel?
- Do you notice any weathering?
Granite
Granite is a type of igneous rock, which means it forms from magma (hot melted rock) deep inside the Earth. It cools slowly, so it has big crystals that fit together like puzzle pieces. You can usually see these crystals with your eyes. Granite is often light-colored—most of the time it looks white, gray, or pink.
The main minerals in granite are feldspar, quartz, and mica. Because it’s so strong and lasts a long time, granite is one of the most common rocks used for headstones today. On the Mohs scale, which measures how hard a rock is, granite scores between 6 and 7.
Look at the LYON headstone.
- How does the stone feel?
- Do you notice any weathering?
- What color is the granite here?
- Why do you think that Sandstone and Granite, which rate similarly on the Mohs hardness scale, have such different rates of weathering?
To log this Earthcache
Please send me an email/message with the GC code and name of this EC with the answers to each Waypoint question. No Armchair caching, you must visit the site. You may go ahead and log after sending me your answers in the message. Please DO NOT post the answers in your log. Thank you for visiting!