Image: Halliburton. Downhole camera technology puts eyes underground, enhancing a company's understanding of what is going on within the furthest depths of production and helping operators make important decisions that benefit from the all too valuable sense of sight.
Barium was discovered by Sir Humphrey Davy at 1808 in England. Origin of name: from the Greek word barys meaning heavy Baryta (barium oxide, BaO) was distinguished from lime (calcium oxide, CaO) by Scheele in 1774.
Erbium was discovered by Carl G. Mosander in 1842 at Sweden. Origin of name: named after the village of  Ytterby  near Vaxholm in Sweden. In 1842 Gustav Mosander separated yttria, found in the mineral gadolinite, into three fractions which he called yttria, erbia, and terbia.