Help With My Three Cent Thomas Jefferson

Hello I have a question having white dots on my stamp make it damaged. And what do I look for in determining where the damage came from.

This is called a 'perfin' and is not damage. The SCF Glossary defines 'perfin' as "Stamps perforated through the face with identifying initials, designs or holes in coded positions. Perfins are normally used by a business or government office to discourage pilferage or misuse of stamps by employees. Perfins may be either privately or officially produced."

While some collectors avoid 'perfins' other hobbyists seek them out, especially on cover like yours.
Don

Perfins are quite common and there are thousands of different. Search on that term on SCF for other examples.

This one appears to read L A Co, which might be "Los Angeles County"; someone with more knowledge might be able to confirm or correct that.

Thanks you both very much and I will definitely go read all about prefin

Examples of US PERFINs