Odd 1976 Penny

Welcome blado, more than likely your cent has been dipped. Coated with some other metal. Pictures always help.

in regards to composition, I think weight will be more determinant than photos.
As a reference, I just weighed a pile of 70s pennies. They range between 3.05-3.12 grams.
An off-metal strike should be notably different.

Hmm...well, my advice only works if you have an accurate gram scale.
This is the model I use. But, others will suggest creating a balance with something like popsicle sticks and weigh against another Lincolns from the 70s. I've never done this, but I think you take two bronze cents, attach to each ends of the stick and mark the stick where the cents balance perfectly level. Of course, the one coin has to be permanently attached and not slide, and the test coin must be in the exact spot used to calibrate the level to work. Sound confusing? That's why I simply paid $30 for a scale.

Digital "mail" scales would work too ........