History Actinium was discovered in NUMBER@1 by PERSON@1 , a MISC@1 chemist , who separated it from pitchblende as a substance being similar to titanium -LRB- NUMBER@1 -RRB- or similar to thorium -LRB- NUMBER@2 -RRB- .

Actinium was discovered in NUMBER@1 by PERSON@1 , a MISC@1 chemist .
