How to Draw a Cross-Section from a Topographic Map

stone-mtn-topo-coverI’ve wanted to write this blog post for a long time, but this weekend pushed it forward on my list because of something my daughter said to me. As some of you who follow me on social media may know, my two kids are runners. This past weekend my daughter competed in the Region 4 USATF Junior Olympic Cross Country meet in Tallahassee, Florida. She had a great meet and qualified to run at the National JO meet in December.

As I pulled up the course maps for December in Alabama, I noticed that they were unlike any course map I’ve seen over the years. There are topographic lines on the map! For once, you can look at the map and see where the hills and valleys are on the cross country course. The first thing I thought to do was to make a cross-section of my daughter’s course map to see if it was flat or hilly. We live in coastal South Carolina so running hills can be tough on our athletes. When I mentioned making the cross-section, my daughter said, “you are the only person who would think to make a cross-section of a cross country course.” Really? Certainly, there is at least one other geologist parent attending that meet who whipped up a quick cross-section. Much to our delight, her 3K course looks relatively flat. Yippie!

Making a cross-section from a topographic is not too difficult and can come in handy for hiking, driving, biking, walking and yes, running. All you need is a topographic map of the area, a piece of graph paper, a ruler, and a pencil. There are some great online resources for obtaining topographic maps. I will link to one I like at the bottom of the post.

stone-mtn-topo-smallFor this demonstration, I am using Stone Mountain, Georgia because it has a significant elevation difference than the cross country course. Here is a topographic map of Stone Mountain.

There are three basic steps to making the cross-section once you have your map.


Step 1:
The first step to complete to create your cross-section is to choose a line across the map where you want to view the elevation changes. This could be the area you plan to hike or as in this example here, a line through the highest part of the mountain so that we can get a really good visual of the mountain’s elevation.

Once you choose the area for your cross-section, draw that line on the topographic map using a ruler. Geologists will label this cross-section line using letter designations such as A – A’. You could use “A – B” or “Start – Finish” or anything else you choose.


Step 2:
The second step is to take a piece of graph paper and fold it along one of the horizontal grid lines. I like to choose an area toward the bottom of the graph paper to give myself plenty of room to work. Lay the edge of the graph paper along your cross-section line then mark the locations of A and A’ on your paper. Mark each topographic line or each index line (the darker topographic lines) if there are more topo lines that you can easily use in the construction of your cross-section, on the paper and label the mark with the elevation of that line. In this example, each index line is at a 100-foot interval while the lines in between are at intervals of 20 feet. Because Stone Mountain is very steep, I can mark only the index lines and still have a nice representation of the height of the mountain. If your area is flatter, you may want to use all of the topographic lines to accurately see the elevation.


Step 3:
Once you mark each topographic line and its corresponding elevation on your graph paper (as shown), unfold the graph paper and make a lined graph above your marks. Mark the elevation of each topographic line on the graph directly above the mark for the line. Once you have all of the dots placed on the graph, simply connect the dots to see a representation of the elevation of the area as shown in the image.

I am not the best artist in the world so your drawing may be a lot prettier than mine, but this will give you an idea of how you can use a topographic map to quickly drawing a cross-section of the elevation of an area. Give this a try the next time you are going for a walk, hike or run in a new area to give yourself an idea of the elevation of the terrain the area.

Topographic Map Resource:






Meet Selenite Gypsum – Our New Favorite Mineral!

selenite-stick-blog-picLove, love, love, love! Did I mention how much I just love these new Selenite Sticks? Selenite is a form of the mineral Gypsum. Satin spar, the more technically correct term for these sticks, is often used interchangeably with the term selenite.  For the purposes of this article, we will use the term selenite or satin spar selenite to keep things simple. Satin Spar Selenite is a fibrous variety of the gypsum mineral which forms in long strands. When the long strands form together in groups, they take the form of these super, awesome, cute “sticks.”

How to Identify Selenite:

Satin spar selenite has a beautiful white color and can also appear colorless. The luster is silky to pearly and sometimes vitreous (glassy). When testing the hardness, use your fingernail to scratch the surface. Selenite is very soft, being a 2 on the Mohs hardness scale.

Locations, Uses, and Cool Formation Features:

Nice samples of selenite are found in locations worldwide including Mexico, Italy, Russia, France, Canada and the United States. Selenite (gypsum) is a common material in paints, tile, drywall, blackboard chalk, fertilizer, and Plaster of Paris.  Selenite is a very popular metaphysical crystal and is associated with the seventh chakra or the crown chakra. The crown chakra is located at the top of your head and associated with enlightenment, cosmic consciousness, energy, perfection, spirituality, and intelligence.

Selenite sticks form in long, prismatic crystals parallel to one another. These mass of crystals form the long sticks. Often, these sticks for in rock seams in the parent rock.

Most of our samples sizes are generally 3-4 inches in length but can vary based on availability and natural crystal shape. You can check out our selenite sticks here.





Luster does NOT mean only shiny!

luster-not-shinyOne of my biggest issues with science teachers in schools today is that they tell kids when they are learning about rocks and minerals that term luster means shiny. Well, guess what, it doesn’t! I wrote a blog post on this several years ago and it is still happening. Again, my daughter came home from school (this time in middle school) with a paper that said that luster was “shiny.” Gag. And, if it isn’t shiny, it has no luster. Double gag.

Every mineral has a luster. Yes, the luster can be shiny but it can also be many, many other things. Geologists define luster as the way light bounces off of the surface of a rock or mineral. Some common lusters are:

  • Earthy
  • Dull
  • Greasy
  • Silky
  • Pearly
  • Shiny
  • Metallic
  • Vitreous (Glassy)
  • Resinous
  • Waxy
  • Submetallic
  • Adamantine

So, teachers and homeschool parents, PLEASE teach kids the correct definition of luster. Yes, it can be shiny but it could also be any of these other terms. Some minerals may even have more than one luster depending on the way it forms. If you have questions, just let us know. We love talking about mineral identification! You can get us at:

Click here to read my earlier blog post about mineral luster.




How to Perform the Geology Fizz Test without Hydrochloric Acid

fizz-test-no-hclGeologists love testing rocks and minerals and, admittedly, one of the most fun tests is the FIZZ TEST. The mineral calcite is made of calcium carbonate (CaCO3).

Hydrochloric acid is the most common acid used among geologists to test whether a rock has any calcite content. In this reaction, the calcium carbonate reacts with the acid and produces carbon dioxide gas, water, and calcium chloride. The carbon dioxide produces the bubbles that you see on the surface of the rock.

Whoa! Hydrochloric Is Too Strong for Kids to Use

We agree with you that hydrochloric acid is not always the best choice to use with kids. For one thing, when kids are learning to identify rocks and minerals you want them to be able to test and explore without worrying if they are going to burn their fingers with acid.

My Solution?

Weak acids like lemon juice (citric acid) and vinegar (acetic acid) are the perfect solution for performing safe lab experiments with younger kids. The only problem with weak acids like lemon juice and vinegar is that sometimes it is harder to see the reaction (the bubbles).

The best way to fix this problem is to create a fresh surface for the kids to test. Since using a rock hammer in class isn’t always advisable, I suggest giving each child a paper clip that they can use to scratch the surface of the sample. When you scratch the surface you are removing some of the older weathered exterior or areas that were already tested and giving the children a fresh surface to test. Once they scratch off a small area to test, they can use a dropper bottle or a straw to place a few drops of lemon juice or vinegar on the surface. If it bubbles, you know that there is the mineral calcite in your rock. This is a great test for limestones and marbles which are made completely of calcite.

If you need help teaching kids how to identify rocks and minerals check out this book which will give you all of the details you need.


Natural Mineral Crystals for Chakra Healing and Meditation

chakra-stones_sept-20-2016_imageThe use of natural mineral crystals in meditation and the healing of a body’s chakras date back hundreds of years. The body has seven major chakra centers through which we gain physical, emotional and spiritual energy. Many people believe that for optimum wellness, it is beneficial to have all of your chakra centers balanced, clear and energized. Each chakra focuses on a specific area of your body and is associated with a different color.

You can use stones of each color to balance, clear, heal and energize your chakras. Clear quartz brings positive energy to every level and can be used to amplify the effect of any other crystal, but is especially associated with the crown chakra. At Mini Me Geology, we have an entire selection of crystals for meditation and healing. We offer both rough and tumbled stones both individually and in kits.

People believe that the seven major chakras are:

1st Chakra – Base or Root Chakra

Located at the base of spine, this chakra is associated with survival, security, and stability and physical energy. Colors:  Red and Black.  Stones:  Red Jasper, Snowflake Obsidian, Obsidian, Hematite, Red Garnet, Black Tourmaline, Carnelian, and Magnetite.

2nd Chakra – Sacral Chakra

Located below the navel or the lower area of your stomach, this chakra is associated with sensuality and sexuality, reproduction, desire, emotions, and creativity. Color:  Orange.  Stone:  Carnelian, Citrine, Red Garnet, Red Jasper.

3rd Chakra – Solar Plexus (Power Chakra)

Located below the breastbone this chakra affects the abdomen, gallbladder, and small intestines. The Solar Plexus chakra is associated with ego, intellect, ambition, personal power, fear, and protection.  Color:  Yellow.  Stones:  Citrine, Olivine, and Aragonite.

4th Chakra – Heart Chakra

Located at the center of your chest near your heart, this chakra is associated with power, love, forgiveness and trust, compassion and courage.  Colors:   Pink and Green.  Stones:   Rose Quartz, Rhodonite, Amazonite, Olivine, Malachite, Green Fluorite and Green (Grossular) Garnet.

5th Chakra – Throat Chakra

Located above your collarbone at your neck, this chakra is associated with communication and expression; guidance and honesty.  Color:   Blue.  Stones:   Sodalite, Azurite, Amazonite, Blue Apatite, Blue Calcite, Blue Kyanite, and Azurite.

6th Chakra – Third Eye Chakra

Located above the eyebrows, this chakra is associated with spiritual awareness, psychic power, intuition and light.  Color:  Purple and Indigo.  Stones:  Amethyst, Azurite, Sodalite, Blue Calcite, Purple Fluorite, and Lepidolite.

7th Chakra – Crown Chakra

Located on the top of your head, this chakra is associated with enlightenment, cosmic consciousness, energy, perfection, spirituality, and intelligence.  Color:  Violet and Golden-White.  Stones:  Howlite, White Calcite, Selenite, Clear Quartz, Clear Calcite, Amethyst, Citrine, and Lepidolite.

Clear Quartz can benefit all chakras by bringing positive energy to impact your entire energy field and amplifying the effect of any other crystal, but especially the Crown.

We have a nice selection of all of the minerals that you can use with your chakra healing and meditation practices. Questions? Just let us know and we are happy to help!

Some Rocks & Minerals May Be Ugly on the Outside but Beautiful on the Inside

Carnelian GeodeIt’s easy to pass by rocks and minerals while you are walking around but you never know what is lurking  inside. Out in nature, most rocks and minerals may look drab and dingy because all of our different weather conditions that will wear away sharp points, dull the vibrant colors and cause cracks in the surface of the samples.

Carnelian is one mineral in particular which looks rather boring on the outside because of this weathering but when you break it open to see a fresh surface, you can see vibrant orange colors and sometimes, a hidden surprise.

Rain, wind, snow, ice, heat and cold all affect the nature and appearance of the Earth’s exposed rocks and minerals.  Rocks that are out in the open will change the way they look due to repeated exposure to the weather over a long period of time.  Hot summers and cold winters will make the rocks expand and contract which can cause cracks and flakes in the surface. The wind, rain, snow, and ice can change the color of a rock from vibrant to dull. All of these processes can also wear away crystal surfaces and change the shape of a sample as well.

When you come upon a rock or mineral and want to get a good look at it, you will need to use a rock hammer (or similar item) to break the rock and collect a small piece.  Look at the fresh surface that was not exposed to the weather to see the true characteristics of the rock.

This carnelian sample is a perfect example of a mineral that looks dull and drab on the outside (top picture) due to weathering processes, but when the sample was broken, we found out that it was actually a small geode with quartz crystals lining an open space on the inside (bottom picture). Look closely at the picture on the bottom, and you can see a beautiful, orange mineral that surrounds the geode center of clear quartz crystals. Carnelian is a natural orangish-red variety of the mineral quartz but not all samples have a geode center. You can learn more about Carnelian and its properties here.

So the next time you are outside, take a minute to look at the rocks and minerals around you. Just because they maybe a dull gray or brown outside, does not mean that there isn’t something fabulous inside waiting to be discovered!

Use Rock Walks to Connect with Your Kids and Science

Rock WalkingLooking for some fun time with the kids away from the television, phones and video games?

Try a “Rock Walk!”

Sure, some people may call them nature walks but here at Mini Me Geology, every walk is a rock walk because we are always on the lookout for great rock or mineral samples everywhere we go.

No matter where you live, you can find at least a little nature somewhere nearby. Even in bustling cities, there are parks with grass, trees, and rocks all around. Parks, trails, mountains, and beaches are just a few of the great places you can take a Rock Walk with your kids. You can have fun spending time together while you are getting exercise and learning about nature. Once you find a great place to walk, let you kids explore as you go to see how many rocks and minerals they can find. Take along zip bags to keep their favorite samples for their collections.

But there are no rocks around us!?!

Yes, I get that not every town has great rock outcrops or pebble-filled rivers to explore, but you can at least find the building blocks of rocks. For example, we are located on the coast of South Carolina. If you have ever been here, you know that there are no rock outcrops. But we do have great trails and beaches where we can find sand, which is the building block of sandstone and quartzite, silt which is the building block of siltstone and clay which may someday become shale or slate.

When you get home with your zip bag of goodies, you can help your kids break open the rocks to see the inside. Usually, a fresh surface will show you the features, colors and textures of the rock better than a dull, weathered surface that was subjected to wind and rain for years. Always be careful when you crack a rock sample. Wear safety goggles and wrap your rock in a towel before you hit it with a hammer. Before you give your kids the cracked sample, check for sharp edges. Rocks with hard minerals, such as quartz, may have sharp edges. You can easily file or sand the edges to make them smooth.

And, okay, if you absolutely must take your phones with you, use the camera to take some pictures of the samples you find and send them to us either here on the blog or on our Facebook page!

If you need help identifying your samples, download our free Rock and Mineral Identification Flow Charts or post your pictures and we will help you out.

Happy Rock Walking!

Use these cool new tools to discover the name of your mineral!

Accessories Kit Blog Image_August 21 2016

As someone who loves rocks and minerals, finding a new sample is super exciting. Geologists use some very basic tools to help them determine the name of a rock or a mineral. Identifying a sample starts with discovering the names of the mineral or minerals, in the case of rocks.

The tests that geologist use for minerals include:

Examination: Use a hand magnifier to determine luster, cleavage, shape and color of a sample. A rock hammer is sometimes helpful in determining cleavage and color if you don’t mind breaking your sample.

Hardness: Use the Mohs Hardness Scale, old pre-1982 pennies, paper clips, glass plates, and your own fingernail to determine the hardness of your sample.

Streak: Use white and black streak plates to determine the streak color (the color of a mineral powder) to help make an identification.

Fizz Test: Use fresh lemon juice or vinegar on a fresh surface of your sample. Hydrochloric acid is the most common acid used by geologist but it is not easy to purchase and lemon juice and vinegar are a better choice for children. Since lemon juice and vinegar are a weaker acid, use a paper clip to scratch the surface of the sample to removed any weathered outer layer. The lemon juice or vinegar will react best on a fresh sample area. Remember, if your sample fizzes, it is made of calcite!

Mini Me Geology’s new Rock and Mineral Testing Kit has everything you need to get started with identifying your samples.

Each Kit Includes:

      • Mini Me Geology Hand Lens with 3x and 6x magnification helps you see your samples closely,
      • Pre-1982 age penny,
      • Large metal paperclip,
      • Glass plate,
      • White streak plate,
      • Black streak plate,
      • Information cards that teach you about the Mohs Hardness Scale and how to perform each test. These cards include instructions for hardness testing, explain how to perform the streak test and how to focus your new hand lens so you can see the details of your rocks and minerals.

As you gather your data from testing each sample, a flow chart is a helpful tool to find the final identity. Mini Me Geology has free basic identification flow charts that you can download and print. For advanced studies, we also offer identification posters which explain the properties 10 of the most popular minerals. We also have posters for igneous rocks, sedimentary rocks, and metamorphic rocks.

If you need help testing your samples, you can always contact us and our geologist will help you!

Our Newest Mineral Kit: Mineral Observation, Hardness & Streak Testing Kit

Hardness Kit Key Image_textWe are thrilled to introduce our latest mineral kit, the Mineral Observation, Hardness and Streak Testing Kit. This new kit will teach your kids to make scientific observations, test the hardness of minerals using the Mohs Scale and the using streak plates, and compare the properties of the samples in the kit. The kit includes eight mineral samples from the Mohs Hardness Scale: talc, gypsum, calcite, fluorite, apatite, feldspar, quartz and corundum. You also receive a hand magnifier, white streak plate, black streak plate and information cards with details on each mineral sample and instructions on how to perform the tests.

Mineral Observation
The hand lens with 3x and 6x magnification helps you see the samples closely while you explore the world of minerals. To examine the minerals, look through the larger, 3X, area of the hand lens first.  This section magnifies the sample to a size three times larger than actual. If you want to see part of the sample even more closely, use the smaller, 6X, area which magnifies the sample to six times its actual size.

Mineral Hardness
Mineral hardness an important key in the identity of a sample. Friedrich Mohs
, a German geologist, developed the Hardness Scale in 1812. The Mohs scale is a relative scale which lists the hardness of 10 common minerals. Talc, #1 on the scale is the softest and diamond, #10, is the hardest. Other common household item have also been assigned to the hardness scale such as glass, fingernail and  penny. The information cards in the kit include a copy of the Mohs Hardness Scale and instructions on how to use the minerals and household items to determine the hardness of each sample. Hint: each sample has a different hardness.

Mineral Streak
Mineral streak is the color of the sample in powdered form. Usually, you use a white streak plate for dark minerals and a black streak plate for light colored minerals. As you scratch the mineral across the plate, a small portion will break apart and form a powder on the surface of the plate. This powder color is the streak. Often, the streak is the same color as the mineral; however sometimes the streak color is different than the outward appearance of the mineral which is a great clue to the mineral’s identity.

Need Help?
The mineral samples are not identified when you receive the kit because we want you to use the hardness and streak test to help you determine the identity of each sample. If you need help, the image shown above identifies each sample. The samples in your kit should look very similar. As always, if you have additional questions about using the Mohs hardness scale or the streak plates, please contact us and we are happy to help.

Moooom, I’m Soooo Booooooored!

Rock DetectivesHave you heard it yet? “Moooooom, I’m Soooooo Booooooored!” It doesn’t take long for kids to get bored once school is out. Keep them busy and save summer boredom with the Rock Detectives kits! Each kit has hours of activities and fun to keep your kids busy all summer long. They will even learn something, but you do not have to tell them that.

We have six Rock Detectives kits to occupy your kids this summer. They are:

  • Mineral Mission
  • Crystal Experiments
  • Crystal Geometry
  • Igneous Investigation
  • Metamorphic Mystery
  • Sedimentary Sleuthing

Each kit has a theme and will teach your kids about a different type of rock or about the unique properties of minerals. Every kit has 6 or 7 Large Mineral or Rock Samples and a Mini Me Geology custom Hand Lens with 3X and 6X magnifications.

The best part of each kit is the 30 page, full color E-book on CD. The printable E-book includes:

  • rock and mineral information
  • sample identification activities
  • word puzzles and mazes
  • coloring pages
  • experiments
  • an adventure story writing exercise for your geology detective
  • activities including making a personal geologist’s field notebook and your very own rock collection box

Whew! That’s a lot of fun!

You can preview the E-books for all of our kits by clicking here. Questions? Just email us and we will help you with anything you want to know about the kits. Happy Summer!