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Refining Borax

Workers refined borax by separating the mineral
from unwanted mud and salts, a simple but
time-consuming process.

The Process

Workers heated water in the boiling
tanks, using an adjacent steam boiler.

Winching ore carts up the incline,
they dumped the ore into the
boiling takns.

Workers added carbonated soda.
The borax dissolved, and the lime
and mud settled out.

They drew off the borax liquid into
the cooling vats, where it crystallized
on hanging metal rods.

Lifting the rods out, they chipped off
the now refined crystallized borax.
To produce "concentrated" borax,
they repeated the process.

For later transport, the workers
bagged and stored the refined or
concentrated borax in a barn that
stood behind you.

Borax will not crystallize at
temperatures above 120 degrees,
so Harmony Borax Works stopped
operating during summer.

To keep the crystallizing vats
cool the rest of the year, workers
wrapped them with water-soaked
felt padding visible in
the photograph.

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