I recently acquired a half bottle of this whisky in a present. Can you tell me anything about it - I reckon it is probably 30yrs + I have tried to find a date on it but can't see one. Also the top which is untouched looks more like the top you would find on a corked wine bottle. It also states it was distilled in Scotland & bottled in the uk under government supervision. Is it rare & does it have any monetary value? Thanking you in advance