Oxides of iron and titanium are responsible for this.
Magnet sticks to granite.
Now i am 99 sure they are not from space but he won t believe me until i can explain to him.
Probably magnetite an fe containing mineral.
Granite can be slightly magnetic.
We have some useless fridge magnets shaped like giant clothespegs to clip notes reminders shopping lists to useless since they get knocked off the fridge fall to the floor and the magnet pops out of the casing.
If you bring rare earth magnet towards it the magnet attracts.
Especially if it is mined from india.
My son 8 found some neat rocks out back and he swore they were meteorites he watches that old meteorite men show so he asked to try with a magnet.
Having dinner this evening around the granite kitchen worktop bar.
I humored him and did so but they actually stick.
Iron oxide is a fair permanent magnet ferrite magnets so if there is iron oxide in the granite it will be weakly magnetic unless the granite is laid.
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