Old friend born in October might get one (4)

I believe the answer is:

opal

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'born in october might get one' is the definition.
I can't tell whether this definition defines the answer.

'old friend' is the wordplay.
'old' becomes 'o' (common abbreviation eg in OE for Old English).
'friend' becomes 'pal' (pal can mean a friend).
'o'+'pal'='OPAL'

Can you help me to learn more?

(Other definitions for opal that I've seen before include "Type of gem" , "Lustrous stone" , "Gem stone" , "often semi-transparent" , "Translucent gem" .)

I've seen this clue in The Irish Times.

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