South American Simple Errors On Stamps

Hello
I've read here a few reports of errors on stamps - are these errors common and only lowers the stamp's value?
Upper left - misplaced cutting of the stamp. I read it was hand made of a coil, so reasonable.
Upper right - couldn't find catalog indication of unperforated sides of this stamp. I'm using simplified Scott and SG catalogs.
Bottom stamps - there's a missing part in the horizontal line of the "A", compared with the right side stamp that has normal "A". Is it a significant error?

Neither are considered errors - but they are freaks.
The right hand yellow stamp looks like it has been cut with scissors; I think I can still see part of the perforations.Hard to tell if the background is almost the same color as the stamp, a black background is preferred.
The blue stamp with the part of the A missing is probably just missing ink.
These "errors" would be very attractive to a specialist that studies these stamps, but it is doubtful that it ill increase the value of the stamp.

Peter

Hi Rob Roy

I collect Colombia. As Peter4522 stated, they are interesting by not valuable.

1. A lot of imperf between (horizontal and/or vertical) exist on early stamps of Colombia. One has to realize that at this point in time tecnology was a little primitive and not as sophisticated as European countries.

2. The 1/2centavo yellow probably comes from the bottom of the plate.

3. The 15c overprinted. The "A" is for Avianca. These are also overprinted with an "L" for Lansa Airlines. I agree that it is just missing some ink and does not increase the value. You will find the overprint doubled, inverted, etc..

Jerry B

Here's maybe a better scan of that stamp. Does it shed more light whether it was cut or end of a plate/coil?

I do not believe it was a coil. It looks like somebody cut it with scissors.

Peter

Thanks. Another filler to my collection.