1944-D Lincoln , Intrinsic Metallic Inclusion

Thanks for the great comments all !
I posted this coin on a group site frequented by Mike Diamond and this is a quote from his comment.

"I can't rule out an intrinsic inclusion, although I doubt it's metallic. I think it more likely that this is a rolled-in contaminant. The embedded material doesn't look like metal -- even corroded metal. The material doesn't dive beneath the normal metal, as some intrinsic metallic inclusions do. But this is not a reliable diagnostic. The alignment of the foreign material with the "grain" of the coin is consistent with both an intrinsic inclusion and a rolled-in contaminant."

Update
A coin of the same date and mint , with a similar inclusion as my coin posted above,was posted on a Facebook group. With that person's permission I'll post his photos here to compare.
These two coins could have come from the same roll of coin metal.

Talk about sister coins! Looks like exactly the same thing and tend to agree with your hypothesis.

Looks like a splash of solder to me, but what do I know?

It doesn't look like metal to me, even oxidized zinc. Since it is aligned with the "grain" of the coin, it's either a non-metallic intrinsic inclusion or, more likely, some kind of contaminant that was rolled into the strip. It's easiest to diagnose an intrinsic inclusion if the normal metal closes over it to some degree, or if the inclusion dives beneath the normal surface. This material appears to be fully exposed on the surface.

In addition Mr Diamond.
Look at the rim over the word GOD on the example that I spotted on Facebook . It appears that the anomaly has extended under the normal surface and appears again at the rim.

Many thanks sir for taking a look!

Many thanks CoinHI !