There is an online dictionary which says you can spell it either CRYSTALLISED or CRYSTALISED, though the double letter spelling is the more familiar. The single letter spelling could be an American usage _ American English often uses one "l" where British uses two, as in traveling/ travelling.
You can also spell it with "s" or "z" - CRYSTALLIZED or CRYSTALLISED - both seem to be about equally common.
What is odd is that other variants of the word, like "crystalline" always seem to be spelt with two "l"s.
In case I've missed anything, you might like to check it out at
ww.wordreference.com
You can also spell it with "s" or "z" - CRYSTALLIZED or CRYSTALLISED - both seem to be about equally common.
What is odd is that other variants of the word, like "crystalline" always seem to be spelt with two "l"s.
In case I've missed anything, you might like to check it out at
ww.wordreference.com
