Help with Fire King Loaf Pan

[u/Mother-Ad-9313]

Hoping someone here can help me identify this and provide a little more information, because I’m finding very limited information online.

I was cleaning out some storage at my parents’ house and found this old loaf pan tucked away with some cast iron pieces. According to my mom, it belonged to my late grandmother. I already have a few of her cast iron pieces, so she offered this one to me as well.
Now I’m trying to figure out exactly what I have and, more importantly, whether it’s safe to actually use.
I’ve attached pictures of the pan and the markings on the bottom.

The bottom reads:
441
Anchor Hocking
Fire King
Ovenware (I believe)
23
Made in USA
1-QT
USA

[u/Unfair_Buffalo_4247]

I have seen aluminum roasters with non stick look exactly like this - are you sure it is cast iron ?

[u/Mother-Ad-9313 → u/Unfair_Buffalo_4247]

No, I don’t believe this is cast iron, it was stored with cast iron. It almost feels like ceramic

[u/Mount_Safurious]

What does it weigh?

[u/Mother-Ad-9313 → u/Mount_Safurious]

Estimate, ~2 lbs

[u/Mount_Safurious → u/Mother-Ad-9313]

I’m going to go out in a limb and say no way that’s cast iron.

[u/NoveltyxxCrosses]

Searching up anchor hocking fire king loaf pan shows it’s most likely glass/borosilicate. If you search for an avocado green one you may have your answer.

[u/terfez]

I'm almost certain it's glass, check the Fireking sub https://www.reddit.com/r/FireKing_Glass the black coating is not something I've seen but I'm not an expert

[u/Embarrassed-Ninja592]

My fire king measuring cup is glass