Abstract: A tag structure for labeling an article cast from molten material including a portion which submerges in the molten material and a portion which contacts the surface of the molten material, and preferably floats on the surface of the molten material. The submerged portion forms a bond with the material forming the article as the material solidifies. A bath of the molten material is provided and the tag is brought into contact with surface of the molten material in the bath, for example, it is dropped onto the surface of the molten material in the bath. The tag if dropped sinks under its own weight into the molten material forming the bond noted above. The portion of the tag which is not submerged bears information relative to the article to be formed. The completed article has, therefore, a tag firmly attached thereto which is placed on the article during formation of the article and not thereafter.