Call me crazy

[1gtsfan]

justafarmer this is quite impressive, is it possible to use this to identify RPM's?

[lara4228]

Yes Rock but so is CC for attributing as well, it's only a database, and all the reference books.

I kind of like Farmer's idea. But, like Rollem said, how much time does it take to formulate and then correctly attribute?

[Rollem]

Casey I am sure it could be done, I have even thought about graphic software I help develop that cut wall paper to the 1000th.

Maybe the mint has specks on dies and could give some definition. But I wouldn't want to lose the fun of reasoning between eyes and knowledge.

My hand held scope shows things that aren't there. Effected by light and angle that when I examine under microscope or loop tell a different story. But I must add that the excitement sure is good during the times of uncertainty.

Please don't take my post wrong Farmer's idea is great..and has a lot of potential..

I like coin counters but out of about 22 $50 bags I have collected over $330 in dimes. Now that was some ones dimes thought by counter to be 1 cent each, I don't if I were counting I would have made that kind of error.

I was just thinking this morning that when I started a year ago I remember seeing coins that I now would love to have. Say like a 1995D with B and E in liberty looking very doubled.( Yep rookie mistake) But with the help of books CC and this forum I don't make now

So the fun is the search to me, but I would love to have any appliance that would keep me from passing and variety.
If all these "Old Boys" had not missed errors I would have to wait for the NEW ONES. LOL

BTY: I know at least 6 people in my area Hoarding anything below 1982. So be prepared they are disappearing.

James

[pman860507]

Yes Rock but so is CC for attributing as well, it's only a database, and all the reference books.

I kind of like Farmer's idea. But, like Rollem said, how much time does it take to formulate and then correctly attribute?

it would take quite a bit of time just like any other resource. for someone who knows CAD it can be done quicker then writing a book probably.

[papascoins]

Wow! That's cool! And I thought you were 'Justafarmer'! I can see it happening more in the near future. (Just press a button and--the microscope will scan the coin for you!!)
Thanks. You are more than 'justafarmer'!

[foundinrolls]

I saw no mention of the fact that mint marks, prior to around 1990 were punched into each working die, by hand, by the staff at Philadelphia, prior to being shipped to the branch mints. That means that even on legit coins, the mint mark positions can vary.

There are 4 known positions for the S on legit 1909 S VDB cents for example. There can literally be a thousand different positions on some dates as the mint mark was added die by die.

You would need to catalog every known variation of mint mark position for this to work.

Also, there would be much duplication as the master hubs were used for many years so that some of the coordinates used would be identical from year to year.

Also, there are numerous die struck examples of 1909 S VDB cents and 1955 DDO cents, for example that are about perfect in every way. This system would pass one of those fakes as real.

It's an interesting concept but it would not be as effective as learning about the coins being checked and just using your own eyes.

Thanks,
Bill

[coop]

1989 Was the last year mint marks were punched.

[lara4228]

Yes there would be a lot of variables that may not be accounted for if a program such as CAD were designed for attributing. And a lot of loop holes as well.

And you're right Bill about it not being effective as using your own eyes, but I think the conceptual idea was not about using it on every coin you have but rather on attributing the coins you suspect to be a DDO/DDR or RPM once you have generically spotted it through your loupe/scope.

[jfines69]

This is a very cool idea... As for the database they are already out there it is just a matter of either building your own or getting permission from the owners of the databases already in use... Just imagine how much time it would save searching for a 1960 RPM... All the program needs to do is get you in the ball park... The home run is up to the individual!!!

[Scott99]

I think this would be a great way to VERIFY a variety, but not something that would be ideal for searching every coin in a brick with. I've been doing cad for 13 years and to me it seems very logical to use it for verification purposes (especially RPM's).

Thank you for sharing the idea! I think I will have something to work on while I wait for banks to open.

[foundinrolls]

1989 Was the last year mint marks were punched.

Yep, I fixed my typo:-) Thanks:-)

[jcuve]

Some interesting points in this thread and I have a few thoughts.

From what I see, the proposed database and subsequent scanning of coins with known varieties on those minted prior to 1990, could be used as a tool along with proper examination. I say proper examination as one would probably be advised to double check, at least quickly, that what was identified as a variety was in fact the actual variety. Probably the best use of such a database would be to scan for RPMs on years where there are hundreds of listings; if one has an unknown RPM, this scan method would make short work of identifying it (1960D would be a great year!). I can see as suggested that verifying coins minted in years with low mintages (such as the 1909S VDB) would be easier so long as you have all the known mintmark locations.

Such a CAD database and scanning comes with the above noted caveats: it only works if the database contains all known varieties (a challenge) and that they are attributed correctly; it would miss any variety not previously documented; it would not work on coins that do not have mintmarks, such as those minted after 1989 or if the coins did not possess some other die specific variable that can be evaluated by the CAD system; one could possibly get a false positive on a non-variety coin if by chance a mintmark was positioned in exactly the same location on a die that was a variety.

[papascoins]

Jason, that sounds like you would go along with this system to a point, while considering all of the variables that would need written in the database. You are definately an exact attributer--dealing only with facts and specifics. This actually is an exact science to the point of dealing also with the many variables that can happen at our wonderful mint.
AND..........what time do you quit at night?? Geez! This late, and still answering questions with great thought and accuracy. Well for me, I'm done for tonite. I'm goin' to bed.
Great readin' and 'learnin' for me!! Thanks!

[Justafarmer]

I have noticed over the years variety collectors use all sorts of tricks grids, straight edges and overlays as tools in their attribution process. Over the last couple of years I have introduced a new tool into my attribution process which I would like to share and seek input from the community.

Everyone knows that 1989 and before for Lincoln Cents and 1990 for most other US coinage mint marks were hand punched into working dies. All other design devices in 20th century US coinage originate from the Master Die. This makes their positioning within a coin’s design fixed relative to each other. Being that the mint mark is not added to the coin design as part of the master die production process its position naturally deviates from one working die to another. So I ask the question - what is the probability a mint mark is hand punched in the exact same location in the exact same orientation on two separate working dies in the same year? With a CAD system you have the ability of measuring in microns.

I may have misled people in my original post. This is not something to replace visual verification of die attribution. I haven’t been able to get the process that precise as of yet. I think that maybe it can but that would involve developing algorithms and unlocking aspects of CAD that this dumb ol’ farmer just doesn’t understand.

So now you may be asking yourself what good is this tool if it doesn’t return the variety your target coin is? Well it eliminates the varieties it is not and produces a ranked list of varieties the coin could be. So I guess the best way to explain it is the process tells me what the coin is not. Someone in a response asked about the 1909-S VDB which has 4 known mint mark locations. I cannot use the process to verify a coin is a real 1909-S VDB but I can use it to verify the coin is a counterfeit.

My process involves using the precision of a CAD system (I use TurboCad which can be purchased off the shelf for under $100.00) by importing pictures and plotting the coordinates of the mintmark to determine its location relative to set points of the coin's design. These coordinates are then searched in a database of known examples. Sorta like a GPS/Triangulation/Fingerprint/CODIS system for variety attribution. I know the explanation below appears complicated and time consuming but actually it is not. Once you’ve got a couple of plotted coins under your belt – you’ll get to the point where it only takes two or three minutes. I am sure there are members here who are a lot more proficient with CAD than I am due to the fact they work with it on a regular basis. And there are features bundled inside CAD software if utilized could make my system better. Any input and suggestions would be appreciated.



The image provided with my post degraded significantly when converted from TCW to JPG.

Step 1 Scan Coin
Step 2 Import scan of coin into CAD system
Step 3 Plot a point on the southwest corner of the (I) of (IN) on the motto. Point (A) on image.
Step 4 Plot a point on the southeast corner of the last (T) of Trust in motto. Point (B)
Step 5 Draw a straight line from point (A) to point (B)
Step 6 Pull a perpendicular line to the south off the line tangent to the west border of the (1) in the date.
Step 7 Draw a line parallel to line (AB) tangent to the north border of the (1) in the date.
Step 7a The two lines drawn in steps 6 and 7 will be your (X) axis and (Y) axis.
Step 8 From the intersection of lines drawn in step 6 & 7 (point C) draw straight lines to point (A) & (B)
Step 8a The triangle ABC created in step 8 is utilized for scaling purposes. Physically drawing triangle ABC is not necessary. But has been done for illustration purposes in the attached image.
Step 9 Draw perpendicular and parallel lines boxing in the mintmark at the northern, eastern, southern and western most tangents.
Step 9a The coordinates of the intersections of the four lines drawn above in step 9 as indicated by points (D), (E), (F), & (G) in the illustration provided is the information of interest. These points provide information of both the location and orientation of the mintmark in relation to the other design elements of the coin. Visualized pivoting the mintmark clockwise or counter clockwise on the image provided. As the mintmark is rotated you can visualize how points (D), (E), (F), and (G) would move north, south, east or west accordingly.
Step 10 Search coordinates of points (D), (E), (F), and (G) in a database on known examples.

[Wayne]

OK I will

You're Crazy