410 Scientific Intelligence. 
and consequently occur in a portion of the spectrum which can only be 
rendered visible by unusual methods. The authors have found the metal 
in the greatest quantity in the lepidolites; that of Rozena, in Moravia, 
contains about 749 of its weight of oxyd of rubidium—the Saxon 
lepidolite appears to be still richer. Traces of it are found in almost all 
mineral waters, but it does not appear to be always presentin the potash 
compounds of commerce. The compounds of Rubidium are most easily 
obtained pure from lepidolite. The rubidium is contained with small 
portions of Cesium in the precipitate of chlorplatinate of potassium 
obtained from the mineral. The chlorplatinate of potassium requires 
nineteen times, the chlorplatinate of rubidium one hundred and fifty- 
iling water for solution. The precipitate 1s to 
simply poured off from the precipitate, which exhibits in the spectral 
b 
b A, soon appear, together 
with several others which are Jess characteristic. The chlorid of rubidium 
extraction with water. In this manner the authors obtain from 15 
kilogrammes of lepidolite, about two ounces of nearly pure rubidium salt. 
By repeating the process of precipitatiou with chlorid of platinum and 
iling several times, the last traces of potassium may be removed. 4° 
obtain rubidium free from cesium, salt be converted into car- 
bonate and repeatedly extracted with alcohol, which dissolves the carbon- 
ate of cesium. = 
Rubidium forms with mercury, with the aid of the Voltaic circuit, an 
amalgam of silver-white color and erystalline structure. This ama’, 
quickly oxydizes in the air, decomposes water in the cold and is electro 
ate to potassium, The equivalent of rubidium is 85°36 and its sym 
ol Rb. 
The hydrate RbO, HO-baq is soluble in almost all proportions in water 
and alcohol; -gives off its water of crystallization by heating, oS 
RbO, HO which on farther heating, melts but does not lose is atom 0 
Oe. 
The carbonate RbO, CO, forms indistinct strongly alkaline ee 
2 dditional atom of 
O., forms prismatit 
da cooling, 
RbCl is anhydr ermanent nd orystalli 
fusible, a mpletely 
