Rusty Rocks Earth Cache
Unlike the Rock Cut just meters from here,
this small outburst of Granite and Limestone appears to be rusting and breaking off.
Yep, these rocks are Rusting.....
So just why does a rock rust?
Rust streaks arise when rocks containing iron are weathered. In particular, rocks containing
reduced ferrous iron will often produce rust streaks. Fe2+ reacts with oxygen and water in the
environment, producing Fe3+ ions. Rust is a mixture of Fe3+ containing oxides and hydroxides,
so it forms as a result of this oxidation. Pyrite grains are one common progenitor of rust streaks because
they are easily oxidized to ferric sulfate, which is soluble in water. However,
this salt hydrolyzes easily in water (especially slightly basic water) to form a precipitate of rust.
So the reason these rocks are Rusting is due to High Concentrations of Iron or Pyrite Present. RIGHT?
Could this small out-crop contain very little Iron or Pyrite, but be so rust colored?
You can find the answer out very simply.
To log this Earth Cache you must do the following Experiment and answer the following 3 Questions.
*****BRING A MAGNET WITH YOU TO THIS EARTH CACHE*****
Any magnet will do, but Rare Earth Magnets or neodymium magnets and samarium-cobalt magnets
will work the best.
Your Task
Stick the Magnet on the Rusty Rock and see if you can get it to stay anywhere.
Questions
1) Did it stick? If yes Describe the rock where it stuck.
(Color, Texture, solid or breaking away etc.)
2) In your opinion, what causes the rocks at GZ to rust.
3) Is there and obvious reason that only this section of the rock-cut is rusting?
Please send the answers to me Via my Geocaching Profile.
Do not post the answers in your on-line log.
NON-SPOILER pictures are always welcome, but not mandatory for logging this Earth Cache