First and foremost, obviously the color is different. Black agate is the color of pure ink. It’s a starless night on glossy rock. If the stone doesn’t have a striped pattern, then it’s most likely black chalcedony. If the stone has a striped pattern, but the stripes are white, then it’s likely black onyx. Black agate has dark stripes and is a natural artistic wonder. Other types of agate have slightly different atomic structures, giving them different shades, patterns, or colors.
Stone: Black Agate
Hardware: Silver Electroplated Brass
Stone size: 4cm x 2cm
Weight: 15 gms