Recently while at Death Valley National Park, my wife purchased a geology activity for me to do with our daughter. And since this is a fairly fun and easy activity to do with kids I figured I would pass along the information. You can get the Activity Rocks kit at Amazon right now as well.
Above you have the four rock/mineral based activities that comes with the kit. The rocks/minerals are:
- Magnetite - and a paperclip for magnetic properties
- Pumice - for a floating rock
- Quartz pebbles - for a sparking rock activity
- Dolomite - With a penny for a dissolving and recrystallization activity.
Here is everything at the start. The pumice is floating, the dolomite is sitting in vinegar, the magnetite is magnetizing, and the quartz pebbles are just sitting there. The best part about this kit is after you are done with it you can pass it on to a friend for them to experiment with as well.
Besides the pumice and the magnetite, which are neat, but you can't really do anything beyond float or stick something to it, the real science comes with the dolomite and the quartz.
Here is the dolomite after it had been sitting in vinegar for about a week. The crystals recrystallized nicely on top of the rock. There is also a penny in the solution, which was supposed to turn the crystals blue (due to oxidation of the copper). They did turn blue at first, but only slightly and not really noticeable after a while.
Now the really interesting thing (that I had not realized before), was that when two "tumbled" quartz pebbles (crystal quartz in this instance) are struck together they produce an electrical shock that lights up the pebbles. This was a little hard to picture so I had my daughter take some photos while I struck the pebbles together. Below are the sequence of photos and a very brief video that shows the results.
All in all a fun activity to get your kids interested in the joys of geology and science. Also, if buying a kit like this isn't your style, this post will give you info on how to build a kit of your own from your own supplies.