Such a person is a geologist.
A geologist is a person who studies rocks and earth.
A mineralogist or a geologist.
A person to researches rocks is called a geologist.And the one who studies the rocks and crystals within the rock is a mineralogist.
a person that studies gems is called a gemologist.
A person who studies genealogies is a genealogist.
a person who studies people but not an psychologist
A person who studies philosophy is called a philosopher.
what do you call somebody who studies snails.
A person that studies animals is called a Zoologist.
A person who studies birds is called an ornithologist.
A person who studies birds is called an Ornitholoigst
A person who studies theology is called a theologian.