astroid

The Holsinger meteorite is the largest discovered fragment of the meteorite that created Meteor Crater and it is exhibited in the crater visitor center.

The kinetic energy was enough to plow a crater that big, the meteor, an iron/nickel meteor, was mostly vaporized by the heat. You ever hammer a nail? The head of the hammer gets hot. That's the kinetic energy transforming into heat. Now imagine a hammer strike big enough and fast enough to gouge a crater that size. That's a lot of heat. It's physics.

It's not missing, it's all over Arizona in a billion pieces.

and all they keep was one part of it?

The other parts are simply dust or as small as a grain of sand

it's prolly fake.

http://keyah.asu.edu/lessons/MeteorCrater/KM13.html