If your colt is the thunderer model (you do not say) then it was made in 1902.
100-1000+ depending on exactly what it is.
value depends on overall condition, model ..................
value depends on overall condition.................
Colt revolver44-40serial6423103
300-500
what model, caliber. ????????
100-1000 USD
100-1000 depending on specifics
value depends on overall condition...........
10-1000 USD depending on specifics.
Impossible to value with just the sn and no other description.