What material is the part made of? Gold, platinum, silver? And what is the level of purity of it, and its weight? Now is the time to use your precision balance, not only to establish coin database this latest data but above all to spot fakes. There is frequently an important dissimilarity in mass between a genuine part and a counterfeit.
With regard to old pieces (over 1000 years old), origin plays an important role in their evaluation. If you know the history of the coin and its origin, or if you know the history of its owners coin database , know that this is invaluable information to determine its exact value.
Is your part certified by the NGC or the PCGS? If so, it will certainly be of more value. When a potential buyer finds that the item he is interested in has been certified by a renowned professional body, he will then be in full confidence as to the object. And this trust is often synonymous with higher offers.
Are your current commemorative coins kept in their original packaging? If so, their values will be affected. The packaging of sets of coins or modern silver issues or gold must be in good condition and complete. Sets in their original boxes are generally more sought after than sets without.
Basic notions of economics want to demand to influence prices. The market still plays a key role in determining the value of collectibles. If a piece is highly sought after by collectors, it will logically be more expensive due to high demand. But even if a piece is rare and in excellent condition, it will have little value if nobody wants it. Now that you know more about the factors to consider when determining the value of coins, you can sift through your own collection and find rarities.