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<![CDATA[bead may be obtained with an intermittent flame, and a
still larger quantity renders it opaque spontaneously.
in the reducing flame.
The color of the bead becomes paler, so that a bead, which is
yellow in the oxidizing flame, is rendered colorless. With a
large quantity of oxide the bead becomes white and crystalline
on cooling.
Behavior with Mic. Salt on Platinum wire
in the oxidizing flame.
As with borax. During the process of cooling the color entirely
disappears.
in the reducing flame.
Both, when hot and cold, the bead is colorless, by which
character oxide of cerium may be distinguished from oxide of
iron. The glass remains clear even when containing a large
quantity of the oxide.
* * * * *
2. Oxide of Lanthanum, LaO.
Behavior with Borax on Platinum wire
in the oxidizing flame.
Dissolves into a colorless glass, which, when sufficient oxide
is present, may be rendered opaque with an intermittent flame,
and becomes so spontaneously on cooling, when a still larger
amount is dissolved.
in the reducing flame.
As in the oxidizing flame.
Behavior with Mic. Salt on Platinum wire
in the oxidizing flame.
As with borax.
in the reducing flame.
No reaction.
* * * * *
3. Oxide of Didymium, DO.
Behavior with Borax on Platinum wire
in the oxidizing flame:
Dissolves to a clear dark amethystine glass.
in the reducing flame.
No reaction.
Behavior with Mic. Salt on Platinum wire
in the oxidizing flame.
As with borax.
in the reducing flame.
No reaction.
* * * * *
4. Oxide of Manganese, Mn^{2}O^{3}.
Behavior with Borax on Platinum wire
in the oxidizing flame.
Affords an intense amethyst color, which on cooling becomes
violet. A large quantity of the oxide produces an apparently
black bead, which however, if pressed flat, is seen to be
transparent.
in the reducing flame.
The colored bead becomes colorless. With a large amount of the
oxide, this reaction is best obtained upon charcoal, and is
facilitated by the addition of tin foil.
Behavior with Mic. Salt on Platinum wire
in the oxidizing flame.
With a]]>
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