Here's Another... Small Or Large Date 1970 S

It's a large date.

The reason your first and second coins look different is because your first coin was harshly cleaned, it had been circulated and beaten up a little, and is overall a bad comparison coin to use.

One of the tell-tale signs of a small date is that the tops of the 7 and zero of the date are level with one another. That's the first thing I always see. Second thing is that the 7 on the large date has a crease running across the mid point where the two lines intersect. Your coins don't necessarily show this well because both of them have some wear in that area. The third, and most definitive point is that the inside of the 9 points to the center of the 7 on the small date, and it points beneath the 7 on the large date.

There are a number of different pick-up points that I didn't even mention here because the three things I already mentioned should be enough to 100% accurately tell the difference.

Thank you by the way for the info on how to determine the differences between the two. Hopefully, it will make it easier to spot if and when I do come across one in the wild. :)