Page 27 of 50. Some terminologies.

There are way more words/terms in use than I have room for here. But, here are some which may come in handy as you expand into silver investing. For those who are investing only and not really into the collecting part of the hobby, none of the following will be of any value except to explain why sometimes a coin in an auction is priced higher than a seemingly exact same coin.

Coins.

Certified, slabbed coins come with short abbreviations on the slab from the grading service. A coin may DMPL on it. That means Deep Mirror Proof Like. So, the coin isn't quite a proof but close in appearance. For your investment purposes this will probably not matter since these coins demand a premium and you may never recover the extra money later. But, just wanted you to know this because it comes up often..
Deep Mirror Proof Like.
In advertisements, the sellers use several abbreviations for slabbed certified coins. One, which I find misused repeatedly is OGH. That stands for Old Green Holder referring to a PCGS coin of early issue. The old holders (slabs) were slightly smaller and had a different edge shape. They will not go in the newer storage boxes correctly and would require one of the older, slightly smaller PCGS boxes, or placed inside a secondary holder about which I know almost nothing. I just place them in the older boxes which I happen to have. Those boxes themselves are becoming quite rare, since the size has been changed for many years now.

Unfortunately, many sellers themselves don't understand this, and often describe a coin as being OGH when in fact it is in a newer slab, but has the older "green label". Sellers list them as OGH and it drives me crazy! I try to list all OGH coins on eBay and most end up being just a newer holder with the green label. Those should be simply described as old green label, and not OGH. The coin pictured above is just that.

This is an OGH. Notice how different the edges are from the one above. RB means reddish/brown.
At first, PCGS failed to provide a slab which held the coin tightly but allowed to to rattle around inside just a little. These are called "rattlers" and are, of course, all OGH as well.
Rattler - up-side-down. PCGS would never do that. Coin rattles around and changes orientation. I know how to right this coin. Bought it and did it already in fact.
Many collectors consider that the older holders contain a more valuable coin than the newer ones. Opinions of many are that the experts were more conservative at first, and gave out lower ratings than they did later. This is perhaps true. I have no way of knowing for sure, and besides it would only matter if you were to break the coin out of the holder and get it re-certified getting a higher certification. In many cases you would (could) gain quite a lot of money, since just one increase in grade can raise the value by many hundreds of dollars! It is with this grading "mystery" that some buyers focus on the OGH and rattlers when buying coins, thus making the prices rise a little in the market place.

In a few rare cases the slab itself raises the value to a collector. By hundreds of dollars sometimes. One year PCGS made a different looking holder, then discontinued it. Automatically creating a collector's item.
Rare "Doily" label holder.
 The other brands of holders are something I know little about. I have always focused on PCGS.

FDI. What about First day Issue etc.?  Some coins are listed as FDI. This is supposed to mean First Day Issue. I personally can't imagine why that matters. Yes, they demand a premium after certification as FDI. But, does it really matter? This is something that originated with the coin certification companies to generate interest from what I can tell. How anyone can tell by looking at a coin 'what day' it was minted is beyond me. I'm sure it is because of when it was shipped, but again - who really cares? 

Anyhow, unless you are deeply into the numismatic end of collecting, I say don't waste your money.

FBL means Full Bell Lines. Applies to Franklin half dollars.

FB. Full bands. Applies to both the Roosevelt and "mercury" dimes.  The PCGS "Full Bands" designation for Roosevelts requires that both the upper and lower pair of bands on the torch be distinct and show full separation. The line dividing the bands must be complete and unbroken.

PL means Proof Like. (Pictured above) Sometimes this is called DMPL for Deep Mirror Proof Like. This is a coin which isn't a proof coin, but is one of the first produced off a new die at the mint. While not a deliberately polished die, as in a proof strike, it is none-the-less a very smooth almost polished looking die and will produce a very polished looking coin for the first strikes until it "wears in".

NEVER TAKE MY INVESTMENT ADVICE! 
Consult the professionals