WTF?! same spool of PLA, different ends. Lighter one is completely unusable - jammed my E3D hotend every time after couple of minutes of printing. Is it common issue with filament?
Definitely not!
What brand of filament is this?
Check the diameter. Looks like the lighter section is wider diameter than the darker; could be too wide. I’ve had that problem with cheaper filament. The MakerBot Replicator (v1) jams at 2.0mm.
I’m not sure, but probably it’s from one of the manufacturers in Poland. Extremely cheap BTW 
@Andrew_Plumb diameter looks fine: 2.90 - 2.94mm (it’s 3mm PLA)
You get that sometimes. I have some orange PLA that is pretty unusable. Doing a job overnight and it jammed when the job was 3/4 finished. It wasn’t a width thing. Looks like it didn’t melt when heated up. I did notice that it was pretty brittle.
Cheap filament can be weird. You get what you pay for.
I just had a small spool of clear PLA that was transferred from a large spool literally self destruct in the middle of the print. The filament was a collection of 6 to 10 inch pieces. The original spool is fine though. Different problem though, just thought I’d share in your misery
I’ve had the exact same problem with pla from eBay, its horrible
In fifty years people will look back on your woes and say “thank you for being early adopters.”
A kitchen dehumidifier can remove moisture from PLA.
nvm.
Just experimenting.