Solid almost almost black is often single crystal (pricy).
Solid blue is often single crystal.
Blue and silver flakes (cracked blue ice) is poly/multi crystaline.
The above are usually in squares you can see, with small stripes going 90' to flat silver wires you can see. Multi/poly is most common. Last longer in my opinion.
Maybe 12x12" for 5w, with some wasted space. $60 to $100 maybe.
Amorphous silicon looks like 'crap brown' paint on the other side of the glass with one set of stripes going the same way, but no wires. (look at you solar calculator) Can look fading brown to blue to orangish. But the colors fade into each other. Short lived and more suscepable to overheating, etc. in my opinion.
Maybe 16x16" for 5w, with no wasted space (all 'painted' frame to frame). $50 to $60, almost always on sale for $40 at the mail order junk store we all love.
What I've seen, you can see a crack. It looks just like a crack.
Sounds like amorphous. Fine for small PVs. For a big one, I only go crystaline (single or multi).
G-