By the way, large auction houses do not give responses to 'valuation requests'. They will do written appraisals for a fee, and they will give a value range for items they take on consignment for their auctions. It sounds to me like they had no interest in selling what you have, but without you being more specific, no one can say whether or not there is a market for what you have. There very well might not be, on a level Christie's routinely deals with. There might be a market on eBay. You can easily check that for yourself.
Usually it means ust that - there is no quoted market.
There are no bid nor are there any one offering the stock
This is usually what you hear in the penny stock market
It just means that you should leave them alone and they aren't interested....
whatever you said, they do not have an interest at this juncture