Can you smell it from there?

Sulfur.
From a hot spring near the site of "Thermopylae", where Leonidas bit the dust, or perhaps, the sulfur.

What lurks in geodes?

Celestite -- a strontium sulfate mineral. I've had this geode since time immemorial -- I think I got it on a trip to Nevada/Arizona in 1971. But it didn't occur to me until now, when reading up on celestite for other reasons, that I actually had some growing in it. The crystals are not the hexagonal or triclinic or quartz growth or calcite, but faintly blue, sometimes more prisamatic. It makes sense, as there's plenty of Sr (a fairly mobile element with no where else to go) and S in the volatiles that fill gas pockets and host lavas in which the geodes form. So, I feel quite happy knowing there's a new "rock baby" in my collection that I didn't even know I had.

Precipitous malachite...

This is from Limogardi, and is about two cm long. It is malachite, and seems to have precipitated about some central core that is no longer present. Possibly some sort of copper nail or such? Found in stream bed flowing through all the old Hellenistic era mine tunnels. It's a great area.

A coral's eye view --

-- of coral, if corals had eyes. I don't think they do.
This is Eocene, from near Dotsiko, and the scale is... let's see, the broadest fossil is about half a cm across.
Found in road rubble, the best place of all to look for fossils.

Is this your sole?

Amphibolite -- not garnet bearing, but certainly showing the kind of deformation that happens when one is stuck between an ophiolite and a continental margin.
Note: FIRST the rock was formed from the metamorphism of something like an old convenient basalt hanging around. THEN all the banding was folded and stretched and crumpled like hell. What does this say about the emplacement process, hus, huh, huh?
The width of the photo corresponds to ~5 cm of real rock.

Oh, it's only quartz...!

Yeah, well...
Straight from the scanner. All the lovely colors are internal reflections, and though just sooooo pretty, are not "real."
These quartz crystals, each on the order of 1/4 a cm or so, are growing in a fracture on a surface of Pelagonian schist.

Makes a pretty picture.

The Plates are Moving!

This is a crop of one of my favorite rock babies of all time -- from Dramala, it is harzburgite. The coarse bands are fairly innocuous harzburgite, but the light smoother looking bands are very very mylonitic bands. No, Bob, they might look like dunite, but with a very very very close look, you can see the sugar grained orthopyroxenes. Here also is what's fun: there are distinct fractures crossing the coarse harzburgite that are cut off by the mylonites, hah! This means -- that some brittle features predate this mylonitization (ductile) period. This, I like to think, is a tectonic plate in motion.

Is this fun, or what? For scale, the large chromite grain is about 3 mm across.