The word "cachalong" is a bit tricky to spell. It's pronounced /kætʃəˈlɒŋ/, with the stress on the second syllable. The "c" at the beginning is pronounced like a "k" sound, and the "a" is pronounced like the "a" in "cat". The "ch" is pronounced like "ch" in "cherry". The "a" in the second syllable is pronounced like "a" in "father", and the "l" in the third syllable is silent. This unique spelling and pronunciation make the word "cachalong" stand out in any conversation.
A milk or blue white variety of opal.
Etymological and pronouncing dictionary of the English language. By Stormonth, James, Phelp, P. H. Published 1874.