Indium is a chemical element with symbol In and atomic number 49. It is a post-transition metallic element that is rare in Earth's crust. The metal is very soft, malleable and easily fusible, with a melting point higher than sodium, but lower than lithium or tin. Chemically, indium is similar to gallium and thallium, and it is largely intermediate between the two in terms of its properties.
I 1228 (OTTO) Indium, powder, -100 mesh, 99.9% Cas 7440-74-6 - used in photovoltaics for the synthesis of the semiconductor copper indium gallium selenide (CIGS), which is used for the manufacture of CIGS solar cells, a type of second generation thin film solar cell.