Unknown English Coin (Id: Early 15th Century Half Groat)

The mint city (the inner circle of text around the cross) is "VIL LA CAL IS" - village of Calais. The coin dates from the time when England retained control of the now-French city of Calais (1347-1558).

At 1.1 grams, I think it's too light for a groat - It's about the weight of a penny. It does appear to have been clipped, so perhaps a cut-down halfgroat?

I can't read the monarch's name, but the use of a double-X for a word-separating colon is quite distinctive and should narrow things down.

Henry VI ca. 1422; cannot precisely date due to the mint mark being off the planchet

So-called 'Annulet Issue'

Calais mint.

Clipped half groat. True pennies and halfpennies do not have an outer reverse legend.

Rev cross with three dots in two quarters / three dots connected by an annulet in two quarters
Obv bust with two annulets still clearly visible here

Interior reverse legend: VIL LA XX CAL IS XX

Exterior reverse legend: + POSVI o DEVM ADIVT_OR_E xM x -- (xM) being the scribal abbreviation for MEVM

Obverse legend: + HENRIC x DI x GRA x REX x ANGL x Z x FR - the use of the saltire stops is unique here

cf. Spink 1840, e.g.