osmium

/oz-mee-uhm/US // ˈɒz mi əm //UK // (ˈɒzmɪəm) //

锇,锇片,锇酸,锇的

Definitions

n.名词 noun

1
Chemistry.
- : a hard, heavy, metallic element having the greatest density of the known elements and forming octavalent compounds, as OsO4 and OsF8: used chiefly as a catalyst, in alloys, and in the manufacture of electric-light filaments. Symbol: Os; atomic weight: 190.2; atomic number: 76; specific gravity: 22.57.

But the osmium and uranium alloyed with it are something else.
Osmium 187 was stable, but it wasn't a normally used step toward Mercury 203.
The native alloy of osmium and iridium does not alloy with gold, however, but falls to the bottom of the molten metal.
The gold may contain an alloy of osmium and iridium; if so, it should be weighed and treated with aqua regia.
Even a chemist can see that that means a lack of heavy metals—no osmium, no uranium, no radium.