Little bit light, but if real, a valuable coin https://www.ngccoin.com/price-guide...llar-km-8-1866-1868-cuid-1167071-duid-1409543
The dentices is where many copies screw up. At the bottom of the obverse the dentices look like they disappeared to dots.
The pitting is concerning. The weight as much as it seems to be underweight - I believe it is within acceptable. This is an easily 4 figure coin and heavily counterfeited. This is my example at 13.39g Will have to photograph it again
After increasing magnification, hold 5X up to the screen and you will have the answer as to authenticity. Remember your sand castle building days at the beach.