Sluggish Fly on A Pyritic Boulder

It's not like it's a meme or anything, but I saw a sluggish fly on limestone at Really Going Places — after taking these photos on the first day of November — and thought, what an opportune time to post photos of this fly, also sluggish, on a pyritic parking lot erratic (glacial erratic? not sure).

Iron-stained rock with a large mass of pyrite in the upper right, with fly for scale
(a bit left of the large pyritic mass)..

The same mass with the fly close to a large pyrite cube.

Now the fly has wandered over a bit to the left (out of the first photo's range), and is standing at a small precipice, appearing to check out the tiny pyrite cubes below.

Here, I've had to give the fly a gentle nudge, because I wanted it to move closer to the tiny pyrite crystals (that's how sluggish it was!).

The fly now looks like it's interested in mining the tiny cubes!

And now the fly has moved over a bit back to the right (barely into the first photo), and is checking out a couple veinlets.

And here's one last photo, for those of you who prefer not to see a fly for scale.

The funny, almost sickly yellowish green color on the outside of this rock indicates that you should be able to find some kind of sulfide mineral inside — in this case, a heckuva lot of pyrite. This color can be used as an exploration guide, provided that one wants to find an ore deposit rich in sulfides.