Interesting Items

1 .How to Detect Watermarks on Stamps

Watermarks are created by shapes woven into the wire trays that paper pulp is placed upon to make sheets of paper. When the water is removed from the pulp, the shapes are left on the paper. Since 1840, with Great Britain's first stamp--the Penny Black-- watermarked paper has been used in the printing of postage stamps. Because watermarked paper was not always used, certain stamps are more valuable then their counterparts. This makes detecting watermarks on stamps an exciting pastime for stamp collectors.

2 .How to Detect Fake US Coins

Anybody can detect counterfeit U.S. coins using five simple, inexpensive tools. In this article, I explain what these tools are and how to use them to protect yourself against fake coins and counterfeits.

A Simple Magnet

You can use a simple magnet to rule out many Chinese-made counterfeit coins because about 70% of all fake coins from China are produced with iron-based planchets (coin blanks). Since there has only ever been one single circulating U.S. coin that should be attracted to a magnet (the 1943 steel penny), virtually any U.S. coin that sticks to a magnet is counterfeit.

How to use: You will need a strong magnet to detect small amounts of iron. Hold the magnet near the coin and see if they attract, even a little bit. If the magnet sticks to a U.S. coin, the coin is virtually certain to be a counterfeit. (Note that Canada has been using steel in their coin blanks for decades, so this test has no meaning for many Canadian coins.)

 

A Gram Scale Accurate to at Least One Tenth Gram

Many Chinese Counterfeiters use scrap metal to make their coin blanks. As a result, the coins are usually underweight. The coins can also be underweight for other reasons, such as shrinkage from using cast dies or cast blanks. The U.S. Mint adheres to very narrow tolerances for error in weight and diameter, so any U.S. coin that is off by more than 1% is highly suspect.

How to use: Make sure your scale can weigh to the tenth of a gram (0.10) or better. Do not use diet scales that weigh whole grams because they are not accurate enough. Place the coin on the scale and then compare the weight to the known proper weight standard (see below) for that coin. If it is off by more than 1%, the coin is a suspected counterfeit.

A Caliper Accurate to the Hundredth of an Inch

A caliper is a device that is used for measuring the diameter of a coin. The U.S. Mint was extremely precise in making coins of the proper diameter, so any coin that is too small, even by a little bit, is highly suspect. Counterfeit coins are frequently underweight and undersized.

How to use: Slide the caliper jaws to the closed position and calibrate it to zero (usually by pressing a "set" or "zero" button.) Then slowly slide the jaws open until they are touching the edges of the coin across from each other. Make sure the coin is snug between the jaws (but not too tight) and read the result. Compare your measurement to known U.S. Mint standards for that coin. If the coin is too small, it is a suspected fake.

A High-Powered Magnifier or Loupe

A magnifier that has a minimum power rating of 8x (8 times magnification, or "8 power") will allow you to see details on the surface of the coin that are invisible to the naked eye. Ideally, you should use a 10x or greater triplet loupe, which has much greater clarity (but is also more expensive.)

 

3.How to detect fake China covers? : eBay Guides

Ebay continue to see people bid on China postal covers of dubious provenance and authenticity, such as Large Dragon covers, Red Revenue covers, Dowager covers, CCP Liberation Areas stamps (such as K.HB-4 Soldier of Anti-Japanese War issued in 1938 by the provisionary central post office of the Jin-Cha-Ji Border Area), PRC military postage (M1 Yellow) covers, C94 Mei Lanfang covers, Cultural Revolution W1, W2, W7, W10 covers. Fake postal cancels and/or tampered envelopes were used by philatelic counterfeiters to forge these covers. Apparently, professional counterfeiters know that the easiest way to reap high profits is to put these stamps on old, used envelopes and then put hand-engraved fake postal cancels (or genuine postal cancels with altered dates) on them. I find it frustrating and disturbing that some innocent buyers, especially those outside China, should fall victim to such a cheap and dirty trick.

Many "expensive" covers on the auction block bear telltale traces of forgery. Some bidders were unfamiliar with the Mandarin Chinese writing system, and therefore were unable to detect forged handwritten addresses on the covers. They were unable to tell what type of calligraphic handwriting was genuine, and what was fake. Only experienced collectors with an intimate knowledge in calligraphic graphology are able to recognize forged handwriting. I saw some fake covers on which the addresses reveal the handwriting of counterfeiters whose fingers were probably more familiar with keyboard than with pen -- a clear indication of forgery, as some counterfeiters were probably too young to imitate various types of sophisticated soft-brush or pen handwriting mastered by many individuals from older generations who had good training in penmanship.

Some bidders who were unfamiliar with PRC postal regulations were unaware that PRC military postage (such as M1 Yellow) was strictly forbidden to be used for international mailing. Nor was it allowed for civilian mailing, a historical postal fact that challenges the authenticity of many of the M1 postal covers sold on eBay. This is commonsensical to almost all RPC collectors, which explains why no one bid on those covers bearing M1 Yellow stamp(s) and international addresses. Some bidders lacked a good knowledge in Chinese postal seals, and were unable to detect nonprofessional engraving from the hands of counterfeiters. Please be aware that all PRC postal seals were machine-engraved at state-run professional mills, and their engraving style and quality are clearly different from those hand-engraved by nonprofessionals.

Only those who know the Mandarin Chinese writing system well and possess a professional knowledge in engraving technology and craftsmanship are able to tell the nuanced differences between authentic and forged seals. This is the case even with some professional appraisers without an intimate knowledge in the Mandarin Chinese writing system plus a professional knowledge in engraving technology and craftsmanship.

One of the effective strategies for countering postal seal forgery is a digitized analysis of the scanned picture of the seal(s) on the stamp(s) of a suspicious cover. A digitized analysis will indicate color and/or structural inconsistencies at the pixel level, thus revealing traces of forgery. So far this seems to be the ONLY effective method of detecting forged postal covers from online auctions. 

A professional appraiser of Chinese postal seals should necessarily possess a native-level literacy of the Mandarin Chinese writing system (including both the regular and simplified forms). A mere oral literacy does not help. It is by no means exaggeration that a professional knowledge in the Mandarin Chinese writing system holds the key to effective and successful detection and prevention of philatelic forgery.

Unfortunately, the restrictions imposed by eBay on bidder communication have made it difficult or even impossible for bidders to alert one another about possible forgery, which would virtually give green light to counterfeiters. Adding to this obstacle to bidder mutual alerting is the eBay selling-bidding option of "User ID kept private," which would allow counterfeiters to shill-bid on their own items as a way to gain bidding credibility and induce bidder confidence. This being the case, whenever bidding on "expensive" China postal covers, whether from the imperial era or the PRC period, please exercise extra caution so that you won't fall victim to counterfeiters again and again.