Brown Nickels Found, Unsure Why One Weighs Only 4.52 Grams-Any Suggestions (1964)

Brown nickels almost always indicates a once buried nickel, Enviromental damage.
John1

To CCF , I guarantee those Nickels came out of the ground via metal detecting machines .

If in fact the nickle was unplated when struck; much better photos would be needed to judge this.

Nickels are not plated from the mint.
John1

Thank you all for your responses. I am still attempting to try to navigate the site :-). So, I tried several times to take better pictures and they all come out blurry. I also attempted to crop and increase the size of the pic on the scale and that becomes blurry as well. The thickness and diameter of the coin is the same as a regular nickel. The coin appears to be smooth along the edges and surface. I can see some glimpses of silver around the rim edge. The middle portion of the rim appears to be the same consistency as a brown worn penny under the microscope. I can still see in God We Trust, Liberty and the date of the front (1986), and the words and monument on the back. Outside of the color and weight, it appears a regular nickel. I am attaching pics of it sided by side with other nickels. I am going to try an upload the previous one with the scale as well.

I am so sorry, I had the other quarter when providing the details about the date and seeing silver. There is NO silver on the edge for the one that weighs 4.52 and the date is 1964. The consistency of the rim is the same--looks like a penny under the microscope. Outside the color and the size, it appears like a standard nickel on front and back.

Change in weight due to corrosive loss.