Amazon.com: CMS Magnetics® 1.26" Sphere Neodymium Magnet One Piece - Storage Box Included for Added Safety : Industrial & Scientific
1/8" Sphere Magnet Neodymium Magnet Balls
Amazon.com: Four Brothers Magnetic Hematite Balls - Sphere Magnets for Fun and Scientific and Developmental Learning - Magnetic Hematite Zinger (25mm) : Toys & Games