Uganda
Scott 599
1 shilling
18 Jan 1988
| Mineral Name: | Columbite-tantalite |
| Composition: | Iron manganese magnesium niobium tantalum oxide |
| Nomenclature: | Named after its major chemical constituents, columbium (now niobium) and tantalum. |
| Industrial Uses: | Ore of niobium (columbium) and tantalum. |
| Additional Notes: | Columbite forms a series with the mineral tantalite. Columbite is the end-member with more niobium (at one time niobium was called columbium, hence the name columbite); tantalite is the end-member with more tantalum. Since columbite and tantalite exhibit very similar properties and since a detailed chemical analysis is generally needed to distinguish the two minerals, specimens from the series are typically referred to as columbite-tantalite. |
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Columbite-tantalite Uganda Scott 599 1 shilling 18 Jan 1988 |
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| The stamp shows a natural, unpolished specimen. | |
| http://stampmin.home.att.net/columbite-tantalite.htm | Philatelic Mineralogy | Copyright © 1997-2008 by Richard Busch |