muh = mint unhinged
mnh = mint never hinged
vlhm = very light hinged mint
lhm = light hinged mint
hm = hinged mint with original gum but remains of a heavy hinge
mng = mint no gum
og = original gum
vfu = very fine used - a fine stamp
cto = cancelled to order
fu - fine used - a fine stamp with perhaps a less fine cancel, a missing perf etc
gu = good used some faults,heavy cancel etc
spacefiller = usually a high catalogue value stamp but with many faults
fiscal = a stamp not used for postal services
cat val (cv) = catalogue value ,where given is for mint never hinged even if the stamp is lhm, hm, mng etc, for used it is for a very fine used example
cds = circular date stamp
pmk= postmark
H/S = handstamp
FDC = First Day Cover
FDI = First Day of Issue
SG= stanley gibbons catalogue number
ACS = auckland city stamps catalogue number
YT = Yvert and Tellier Timbres de France 2017 Catalogue number
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