My dad was a trapper when he was young. He says beaver teeth are usually orange and are curved and have a chiseled end where they bite. Hope that helps.
I've found lots of cow's teeth detecting over the years... then again, they may be horse teeth.
My suggestion would be to contact a farm veterinarian or an equestrian center in your area and email them a pic of your find.
Looks like you have a bit of salad stuck in there...
I have no idea what type of tooth it may be, but I don't think it is a horse tooth.
It looks like the enamel is on the smaller end, so that would be the exposed end showing above the gum line.
So....
Nokta FoRs Gold, a Gold Cube, 2 Keene Sluices and Lord only knows how many pans....not to mention a load of other gear my wife still doesn't know about!