24-Chromium Traditional Geocache
-
Difficulty:
-
-
Terrain:
-
Size: 
(small)
Please note Use of geocaching.com services is subject to the terms and conditions
in our disclaimer.
This cache was hidden to help fulfill
the requirements for Boreal Walker's
Periodic Table of Elements Challenge
GC2P5TJ
Chromium is a chemical element which
has the symbol Cr and atomic number 24. It is the first element in
Group 6. It is a steely-gray, lustrous, hard metal that takes a
high polish and has a high melting point. It is also odorless,
tasteless, and malleable. The name of the element is derived from
the Greek word "chroma", meaning colour, because many of its
compounds are intensely coloured. Chromium oxide was used by the
Chinese in the Qin dynasty over 2,000 years ago to coat weapons
such as bronze crossbow bolts and steel swords found at the
Terracotta Army. It later came to the attention of the west when it
was discovered by Louis Nicolas Vauquelin in the mineral crocoite
(lead(II) chromate) in 1797. Crocoite was used as a pigment, and
after the discovery that the mineral chromite also contains
chromium, this latter mineral was used to produce pigments as
well.
Chromium was regarded with great interest because of its high
corrosion resistance and hardness. A major development was the
discovery that steel could be made highly resistant to corrosion
and discoloration by adding chromium to form stainless steel. This
application, along with chrome plating (electroplating with
chromium) are currently the highest-volume uses of the metal.
Chromium and ferrochromium are produced from the single
commercially viable ore, chromite, by silicothermic or
aluminothermic reaction or by roasting and leaching
processes.
Although trivalent chromium (Cr(III)) is required in trace amounts
for sugar and lipid metabolism, few cases have been reported where
its complete removal from the diet has caused chromium deficiency.
In larger amounts and different forms chromium can be toxic and
carcinogenic. The most prominent example of toxic chromium is
hexavalent chromium (Cr(VI)). Abandoned chromium production sites
often require environmental cleanup.
Additional Hints
(No hints available.)