| The thin covering is composed of alternating layers of silicon dioxide and tantalum pentoxide. |
| High voltage and low amperage were used to increase the contrast between the dense tantalum markers and the bone. |
| A previous study of the columbite-tantalite series minerals indicated a similar change for tin, tantalum, niobium, and manganese. |
| The materials all include oxygen, and one, for example, also contains niobium, tantalum, and zirconium. |
| A second element, tantalum, is always present in these minerals along with niobium. |
| His recovery of the rare and vital ores of tantalum, lithium, and beryllium greatly aided the War Production Board. |
