Mica is "the rock that comes in multipage books". What are
the dimensions of this tiny three-page stack of muscovite?
How large is the step from one mica layer to the next?
What are the dimensions and angles associated with the
muscovite unit cell (drawn in blue)? What kind of atoms
make up the "icing" between the layers?
One cool use of mica is to offer
a clean flat surface for scientific experimentation by cleaving
top layers away (e.g. with help from a piece of scotch tape).
Hit reload to view the tilt sequence again, or
simply use the mouse to orient the specimen at will.
Here's an atomic force microscope image of etched mica
showing the layered terrace structure. Each of the three levels is
one "mica page" in thickness.
Here is a low-mag image of an etched alpha-recoil track:
the damage-trail caused by the recoil of
a uranium atom in mica, just as that uranium atom spit out a
helium nucleus during "alpha decay". The slightly darker and
brighter patches in the flat areas away from the pit are
"page thick" terraces like those shown above, and the white
dots are likely particles of some sort on the mica surface.
Here's a closeup of the above etched-track pit that
highlights the single-page steps down into its interior.
Here is a topography image, colored by a lateral force
signal, of some nanometer-thick slippery
patches (white) on a mica. The shallow steps in the foreground are
single-page steps into another alpha recoil track pit.
Even stranger: The shadow in the foreground may be from
the nanohuman photographer who
took the picture...
