These are terms that define the four chip states:
New
NIB: New In the Box or Package, means that the chip, no matter its age, is unused and still in its original packaging.
NOS: New Old Stock, means that the chip, no matter its age and the fact it is not packaged, has never been used.
Mounted
Socketed: The chip, whether it is has been used or not, has been inserted in socket and mounted on a board.
Soldered: The chip, whether it has been used or not, has been soldered on a board.
Pulled or Desoldered
Pull: The chip, whether it has been used or not, has been pulled from a socket.
Desoldered: The chip, whether it has been used or not, has been desoldered from a board.
Refurbished
This is a much abused term. The general meaning is that the chip has been used, but the physical condition of the chip is restored to like-new function (not appearance).
Let review these categories for the purposes of assigning value to chip. The first thing to note is that these states say nothing of the chip’s physical condition. I have seen chips so badly handled that they were reduced to ceramic dust and scrap metal … even though they were “New In the Box”.
New condition, for vintage chips, implies rarity. In the vast majority of cases, far fewer chips still exist in unused form than exist as pulls, desolders, refurbs, or are still mounted on boards, computers, etc. for the use intended.
There is a general debate in the collecting community as to which is better, individual chips or mounted chips. This is an extension of the debate of chip collectors versus computer collectors. There is no doubt value to seeing how devices were used. The value of a new unused mounted chip (implying an unused board) versus new unused individual chip would generally be considered equal. The collecting community generally favors new unused chips over used mounted chips. Other factors that might affect a mounted chip’s value are: reasonable board size, the board’s historic value, and the total condition of the board.
Pulled or desoldered chips are a fact of life in chip collecting. Carefully pulled chips can be aesthetically very pleasing. ZIF (Zero Insertion Force) sockets inflict the least damage, but were rarely used with vintage chips. A chip that has been carefully pulled from its socket generally will have no bent leads and will have minimal lead scrapping, or buffing. Desolders are a challenge. The excess solder left on the leads detracts from the look of the chip and makes it difficult to store without further damage. Gold lead chips are the most challenged of the desoldered chips. A well done desolder is a rare thing, but, if done well, keeps the value of the chip in line with that of a pulled chip.
The purpose of refurbishing chips is to restore the install-ability and electrically connect-ability of the chip. The most damage done to chips in normal usage is to the leads. The most successful refurbishing approach is straightening and re-tinning leads. Refurbishing generally does not address cosmetic blemishes to the surface of the chip. After all, the purpose of refurbishing is to restore function, not looks.