Lodestone is a variation of Magnetite and is highly magnetic, some pieces are magnetic enough to even hold onto iron filings, but not all. These mineral specimens come from Mexico, they leave a black or grey streak. Magnetite is the most magnetic of all the naturally occurring minerals on Earth. Naturally magnetised pieces of magnetite are called lodestone. A form of Iron Oxide it is black or grey with a brownish tint in reflected light and a dull metallic lustre. Historically, lodestones were used as a primitive compass by the Vikings to navigate their longboats. These samples are only available in a small size, approximately 1.5" in size and will come supplies in a card tray with a label.