I would first like to provide this link (alos included in the text below) that has proved invaluable in this research. Library Of Congress This page is for information to which materials the LOC considers 'safe' to use for long term storage. I dont think this was meant as 'all inclusive', but rather what materials they are advising now that Dupont no longer makes Mylar. I would like to explain to everyone what Mylar is. Mylar IS the Dupont company 'trade' name for polyethylene terephthalate. Look at is this way, Kleenex is the 'trade' or brand name by a company for a certain product. If another company makes a similar pruduct, its cannot be called 'Kleenex', although some will still call it so. In the emails below, i campared it to the square/rectangle comparrison. If it helps to look at it this way ... All squares are rectangles, but not all rectangles are squares. All Mylar is polyethylene terephthalate, but not all products made from polyethylene terephthalate is Mylar. The brand name of Mylar, made by Dupont is 'NO longer' made. Dupont makes similar products, but not under the Mylar brand name. So any product out there selling an item they say is made from 'Mylar' is possibly mistakingly calling their polyethylene terephthalate product as Mylar. Not a big deal, as long as the product IS polyethylene terephthalate (this is now a pet peve of mine) What follows below is a conversation i had via Email with Susan Maltby. She is Conservator, Maltby & Associates Inc., and Adjunct Faculty, Museum Studies Programme/FIS at the University of Toronto. Many of you may also know her from Coin World as a contributing columnist. In my conversation with here, she proved to be very knowledgable, friendly, and more then willing to help others learn. My Original Email Susan's response For anyone interested in learnign more about the Beilstein Test or Oddy Test , just click the links. The two sites provided go to great lengths discussing the tests, and should leave you with a full understanding of how they are performed. The Beilstein test will help many collectors correctly tell if the product thyey bought is indeed what they thought it was. My response, with many additional questions Once again Susan responds with answers to my many questions Once again, her response, although bursting with information, left me with additional questions I asked about the heat sealing, because i knew some people practiced this. I was unsure if it hurt, helped, or made no difference. I think Susan answered sufficiently. And Susan's final email before i had to leave for a weekend trip. I want to go on record once again, to Thank Susan for taking her time to answer what may seem like very simple questions to her. Thank you Susan!!! How to use the above information to safekeep your coins? The best environment to store a collection is dark and dry with low humidity and low dust levels. For storage, there are 'alot' of options. Each option has its own collector preferences and its own pros/cons. You might try using 2x2's, a 2" square cardboard holder with clear windows, to house your coins. There are also 2x2 clear plastic flips, 2x2 paper envelopes and clear polyethylene slips 2x3, etc that can be used for short term storage. These can then be stored in plastic pages suitable for a notebook or stored in a row in an aluminum foil box which is also about 2 inches wide. Choices in coin holders include but aren't limited to the following, in 'NO' particular order: * 2x2s. Consists of white cardboard with clear Mylar pocket to allow viewing of coin. Can attribute and describe coins on cardboard with pen or pencil. Called 2x2s because holder's dimensions measure 2 inches by 2 inches, though most coin holders are this size as well. (In Europe larger sizes are available along with plastic shells into which you place the cardboard holder.) Paper dust from cardboard can cause spotting over time, though some holders advertise that they're dust free. Staples on the staple-type 2x2's can scratch coins if you're not careful when removing them. Glue on glue-type 2x2s may damage coins over time from glue vapors. Somewhat chintzy looking but inexpensive and relatively safe. * Safety flips. All-plastic two-part holder -- you flip up part holding coin to view coin's reverse. Can choose flips with one pocket (for coin) or two pockets (for coin and for paper insert on which you can attribute and describe coin, optionally using computer). Called "safety flips" because safe for long-term coin storage. Two kinds: generic safety flips and Kointain type Saflips. Generic safety flips made from low-plasticizer PVC. Often mistakenly called non-PVC flips, PVC-free flips, or unplasticized flips. Much safer than PVC flips for long-term coin storage because of low levels of plasticizers, but not completely safe. Can view edge of the coin. Hard edges may scratch coins when inserting and removing if you're not careful. May crack with repeated opening and closing, forcing you to replace the holder. May turn pale color over time, also forcing you to replace them. Shouldn't be used with proof coins because they can outgas small quantities of hydrogen chloride gas (hydrochloric acid), which can cause microscopic pitting, leading to hazing. Generic safety flips relatively inexpensive. Generic safety flips include: Super Safe brand, made from Polypropylene, (sometimes called Madison coin flips -- made by Frame-A-Coin of Madison, NJ) available at many coin shows and through many online sellers. Come in sheets -- you tear off individual flips. Generic safety flips (made by International Plastics of Altadena, CA) are Thicker and sturdier (they make nice mini-coin stands) than Super Safe flips but crack more easily and not as good for largest coins. Some other sellers of flips sell generic safety flips that they buy from various manufacturers in China. Always be carefull of the material flips are made from. If the seller does NOT say, another seller will. Kointain Saflips are made from polyethylene terephthalate, a type of 'Polyester' and commonly, and mistakingly, called Mylar. Polyester is safer over the very long term than low-plasticizer vinyl. Also, not as prone to cracking. Horizontal striations, however, can be unsightly and may interfere with viewing of coin inside. Sharp corners. More expensive than generic safety flips. * Flips (also called soft vinyl flips). Consist of PVC (polyvinylchloride, also known as vinyl), stabilizers (to prolong life), and plasticizers (to soften the plastic). Plasticizers can damage coins over time (causes "PVC damage," which looks like green goo), with damage occurring faster when flips are exposed to heat, humidity, or sunlight. Soft vinyl flips are used by sellers and in submitting coins to grading services because they make it easy to insert and remove coins and because they're inexpensive. Coins bought in soft vinyl flips should be removed and placed in other storage media. * Air-Tite holders. Acrylic and polyethylene (should NOT be confused with polyethylene terephthalate). Safe for long-term storage. Larger than standard 2x2 format (2-3/4 x 2-3/4 with display card). Can be Expensive. http://www.airtiteholders.com. * Intercept Shield holders. Made with material that's designed to intercept and neutralize sulfur and other contaminants, preventing toning. Can be difficult to place coins inside flexible gasket. Expensive. Can buy separate Intercept Shield boxes to use with other 2x2-size holders or with slabs. http://www.interceptshield.com/products.html. * CoinEdge holders (formerly called CoinSafe). All plastic -- Polyester, remmember polyester does not mean Mylar, or polyethylene terephthalate. Safe for long-term storage. Can view edge of the coin. Chintzy look and feel. http://www.coinedge.com. * Whitman (or Gallery) holders. All plastic (polystyrene). Safe for long-term storage. Coins slide and bang around inside, potentially causing damage. Inexpensive. * Eagle holders. Polystyrene encasing with Polyester (polyethylene terephthalate) windows. Safe for long-term storage. Time consuming to insert coins. Small coins don't always remain in position within holder. Large coins can cause the holder to pop open. http://www.eaglecoinholders.com. * Capital holders. Plastic (Lucite) holder that you screw shut. Inserting and removing coins can be labor intensive. Coins can slide or bang around inside, potentially causing damage. Expensive. http://www.capitalplastics.com/coins. * Kointain holders. Round shell that fits snugly around coin. Non-PVC plastic and safe for long-term storage. Can be used alone or inside other holders or albums. Other coin storage options include slabs, slab-like holders, coin albums, coin folders, paper envelopes, poly bags, coin cabinets, coin cases, coin frames, coin tubes ... and pockets and purses. Because of forums post length restrictions, Part 2 is below.