Pelopic acid

However, the story does not end there. It was not until 1844 when Heinrich Rose (1795-1864) rediscovered the element by producing two similar acids from the mineral niobic acid and pelopic acid. Rose did not reahze he had discovered the old columbium, so he gave this new element the name niobium. Twenty years later, Jean Charles Galissard de Marignac (1817—1894) proved that niobium and tantalum were two distinct elements. Later, the Swedish scientist Christian Wilhelm Blomstrand (1826—1899) isolated and identified the metal niobium from its similar twin, tantalum. 

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