Die clashes are fairly common on early 40’s fifty cent coins.
What you have is a nice one extending that far.

Maybe this will help

www.saskatooncoinclub.ca/articles/05c_1 ... .html#1909

Sp3nc3r
Where abouts in Ontario are you?

As you probably know, condition is the major factor in the value of a coin. A couple of grades can make a big difference in how much a coin is worth. I have to assume that the coins you purchased are of average grade considering where you bought them. If that is the case then I would have to say tha...

Same as your 1944 cent, that is Machine Doubling.

Much better pictures, I wish you had shown those in the first place.
I agree that it is a Struck Through, most likely grease.

Both are low line.
In the future, please crop your photos. This will help increase the size.

Welcome to the forum

Not an error, it looks like some sort of corrosion has attacked you cent.
Possibly been buried or exposed to something corrosive for awhile.

Looks like a small die chip on the post, not uncommon.

I don’t think that is a depression. What I see is an occulated gas bubble to the left of the
date which being higher probably protected the date from the amount of wear that is
apparent on both sides of the coin. What you have is just a well worn quarter.

If they are holes, then it is damage. That could not have happened when the coin was struck.

The coin in the ICCS holder is a 1949, not a 1948

What does the obverse look like.
You should always supply photos of both sides, whether you think it is necessary or not.

Going by the spacing between the denticles, I believe your right.

If that black circle is incuse, it is possible that it is a Struck Through
which would be a minor error.