Summer fun: Topic 3 - Rocks and Minerals

A gift for my birthday, summer 2017.

       
​         Once again, there is so much to do when learning about rocks and minerals.  It's one of my favorite topics.  Even as a child, I loved rocks, and my mother collected rocks from all over the world.  Whenever a friend was going to be traveling somewhere, Mom would ask them to bring back a rock for her, and it seemed as though everyone did.  She numbered them and kept a list of where each one came from.  Many of them migrated to her beautiful rock garden.  When one of my sons became interested, I was thrilled to jump into the topic again.  Now, when you visit my gardens, you'll find all kinds of treasures hidden around my yard as well.
​         We collected gems and ordinary rocks.  We found quartz and granite in our own backyard, took a trip to Thatcher Park and hunted for fossils, went to the Herkimer Diamond Mine, Howe Caverns and the lesser known Secret Caverns, my personal favorite with it's 100 foot underground waterfall.  We also went to The Petrified Sea Gardens which is owned by the quarry and is (sadly) now closed.  There we found fossils of algae that grew at the sea bottom.  They look like fossilized flat roses. You can still find some of these spectacular 500-million-year-old fossil formations, called Stromatolites, at Lester Park in Saratoga Springs.  We also took a trip to Shelburne Falls, Massachusets to visit the glacial potholes found there.  These were formed when the glaciers melted creating whirlpools of rocks and gravel that dug round holes through the rocks.  When we went there, you could still walk out onto the rocks and swim, but alas, like so many things, they stopped allowing that because of too many injuries.  However, Shelburne Falls is a fascinating place to visit anyway with a glass blower, a flower bridge and a great sandwich shop right on the main drag.  All of these places have great educational materials for you to browse.
       Then, don't forget about our own NYS Museum and they're amazing collection of rocks and minerals.  We also have a local rock and mineral club that hosts a show at the museum every winter.  They also hold their meetings there the first Thursday of each month during the school year.  This club is geared more toward adults, but if you're interested in rocks, it's worth checking out.
Here's another resource to find places to hunt for fossils:  ​https://www.newyorkupstate.com/attractions/2015/09/fossil_digs_in_upstate_new_york_5_places_to_look.html
         
        In addition to potential field trips, which are numerous, there are simple experiments that can be done.  Epsom Salt crystals are easy and inexpensive to grow. 

Epsom Salt Crystal Materials 

• 1/2 cup very hot water
• 1/2 cup epsom salts
• Food coloring (optional)

What You Do:

1. In the beaker, stir 1/2 cup of Epsom salts with 1/2 cup of very hot tap water for at least one minute. ...
2. Add a couple drops of food coloring if you want your crystals to be colored.
3. Put the beaker in the refrigerator.
4. Check on it in a few hours to see a beaker full of crystals!

Here's a site on how to make salt & vinegar crystals:  https://​layers-of-learning.com/salt-and-vinegar-crystals/

        Of course, we made lots of rock candy, which are just sugar crystals, and what kid doesn't love sugar?  You can flavor them, color them or just grow them plain.  They are simple to make, but it's important to follow the directions.  Basically, all you need to make rock candy is sugar and hot water.
The color of your crystals will depend on the type of sugar you use (raw sugar is more golden and refined granulated sugar) and whether or not you add coloring. Any food-grade dye will work.

Rock Candy Materials

• 3 cups sugar (sucrose)
• 1 cup water
• clean glass jar
• cotton string, chopsticks or popscicle sticks
• pencil or knife
• food coloring (optional)
• 1/2 tsp to 1 tsp flavoring oil or extract (optional)
• Lifesaver candy (optional)
• pan
• stove or microwave

Make the Rock Candy

1. Pour the sugar and water into the pan.
2. Heat the mixture to a boil, stirring constantly. You want the sugar solution to hit boiling, but don't let it get hotter or cook too long. If you overheat the sugar solution you'll make hard candy, which is nice, but not what we're going for here.
3. Stir the solution until all the sugar has dissolved. The liquid will be clear or straw-colored, without any sparkly sugar. If you can get even more sugar to dissolve, that's good, too.
4. If desired, you can add food coloring and flavoring to the solution. Mint, cinnamon, or lemon extract are good flavorings to try. You can get a natural flavor by squeezing the juice from a lemon, orange, or lime, but the acid and other sugars in the juice may slow down the process a lot.
5. Set the pot of sugar syrup in the refrigerator to cool. You want the liquid to be about 50°F (slightly cooler than room temperature). Sugar becomes less soluble as it cools, so chilling the mixture will make it so there is less chance of accidentally dissolving sugar you are about to coat on your string.
6. While the sugar solution is cooling, prepare your string. You are using cotton string because it is rough and non-toxic. Tie the string to a pencil, knife, or another object that can rest across the top of the jar. You want the string to hang into the jar, but not touch the sides or bottom.
7. You don't want to weight your string with anything toxic, so rather than use a metal object, you can tie a Lifesaver to the bottom of the string.
8. Whether you are using the Lifesaver or not, you want to 'seed' the string with crystals so that the rock candy will form on the string rather than on the sides and bottom of the jar. There are two easy ways to do this. One is to dampen the string with a little of the syrup you just made and dip the string in sugar. Another option is to soak the string in the syrup and then hang it to dry, which will cause crystals to form naturally (this method produces 'chunkier' rock candy crystals).
9. ​You can also use sticks that are propped up against the side of the jar.  These are a little easier for little hands to manage.
10. Once your solution has cooled, pour it into the clean jar. Suspend the seeded string in the liquid. Set the jar somewhere quiet. You can cover the jar with a paper towel or coffee filter to keep the solution clean.
11. Check on your crystals, but don't disturb them. You can remove them to dry and eat when you are satisfied with the size of your rock candy. Ideally, you want to allow the crystals to grow for 3-7 days.      
12. You can help your crystals grow by removing (and eating) any sugar 'crust' that forms on top of the liquid. If you notice a lot of crystals forming on the sides and bottom of the container and not on your string, remove your string and set it aside. Pour the crystallized solution into a saucepan and boil/cool it (just like when you make the solution). Add it to a clean jar and suspend your growing rock candy crystals.

Once the crystals are done growing, remove them and let them dry. The crystals will be sticky, so the best way to dry them is to hang them. If you plan to store the rock candy any length of time, you'll need to protect the outer surface from humid air. You can seal the candy in a dry container, dust the candy with a thin coating of cornstarch or confectioner's sugar to reduce sticking, or lightly spritz the crystals with non-stick cooking spray.

        Check out this site for how to grow alum crystals.  And, if you love these experiments and want to do more, there are plenty of kits to buy with all of the materials you need.  There are magic rock kits and kits that have you growing crystals on absorbant paper.  These have been popular with my family especially during the winter holidays.  The main thing is, be sure to have lots of fun while exploring the exciting world of rocks and minerals.