Questions on Hairlines and Scratches.

Where could I find the following information. I know you're shaking your head wondering why in the world does he want that, but I have my reasons even if you think I'm ! LOL

#1..The average microscopic size range for Length, Width and Depth of Hairlines and Scratches found on coins.
#2..The magnification power required to see these imperfections.

I've pounded the Web for days using a zillion different query statements and questions with no results. I have a hard time believing the answers aren't out there somewhere in cyberspace, but all I get are links that have picked a word from my query that can be connected with something to sell me, or if I try to out smart the &*%# thing by carefully arranging my words and using quotation marks to force it to focus on what I want, it just says "No can do !". Guess I might have to get a new library card if nobody here can help. Thanks if you can.

ToddB67
(Sorry for the rant.)

 

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Unless I can see them with the unaided eye, they don'r exist.........

 

Questions that really have no answer. Scratches or hairlines can have any size, the operating factor is "are they visible". Magnification above 7-10X is excessive.

 

Yeah, those statistics are not something that you'll find.

If you really want to know the answer, Sir Francis Bacon invented the scientific method. Feel free to apply it here, conduct some research, and tell us your results!

 

Not quite true.
A quick look through a 3x loupe can uncover fine abrasive cleaning.

 

I lost my hairlines many years ago.

 

A 10x is more than sufficient.

 

Thanks everyone for replies to this thread !
GDJMSP's was especially informative.

Before posting this thread I had collected some information during my efforts to obtain answers to:

#1..The average microscopic size range for Length, Width and Depth of Hairlines and Scratches found on coins.
#2..The magnification power required to see these imperfections.

So today I decided to publish what I collected FYI (below).

https://www.numismaticnews.net/article/scratches-vary-in-severity-on-coins ← According to the 6th paragraph down on the 1st page of this link, the author says "When does a hairline become a scratch? I believe it happens as soon as the mark becomes slightly wider or deeper – perhaps the thickness of the finest blonde human hair you could ever imagine."
So, according to that statement in quotes, which I interpret as defining scratches, and concomitant with the diameter range of Flaxen hair in the following link below, I have deduced the diameter and theoretically the width at a Min.- Max. level !

See the following quote below that appears at the bottom of the chart in the The Physics Factsbook link below, that I converted to be from 0.0007" (seven-ten-thousandths) to 0.002" (two thousandsths) inch in my Legend below. Hairlines would then be even smaller, perhaps down into the micrometer (millionths of a meter) size !

"Flaxen hair is the finest, from 1/1500 to 1/500 of an inch in diameter … and black hair is the coarsest, from 1/450 to 1/140 of an inch." https://hypertextbook.com/facts/1999/BrianLey.shtml

Legend (Flaxen hair):
1/1500 = 0.000666" (rounded ^ = 0.0007" or seven-ten-thousandths inch
1/500 = 0.002" or two-thousandths inch
Reference: 10-6 = 0.000 001 inch

1 micro-meter = 1 millionth of a meter = (39.3700787401 ÷ 1,000,000.) = 0.00003937007 = (0.000040" rounded ^) = "forty-millionths".

17–50 µm (micrometers) = 0.0007 "- 0.002" diameter range for flaxen hair (blond).
56–181 µm 0.0022" - 0.007" diameter range for black hair.

We have microscopes with multiple-power settings, but apparently no one with access to a professional-quality instrument and having concurrent interest in coin grading has thought it would be of general interest to take on the project of measuring hairline-size imperfections and then published their findings for numismatist !

With the plethora of technical information available on a vast panorama of subjects, I wonder why this has not been done already and at least briefly covered in the Red Books ?

I think I've given a brief coverage here of scratch level width (depth and length being still "up in the air".), but I'll have to rely on someone else to tackle hairlines , since all I have is a kid's toy microscope for amateur work left by one of my sons and now in retirement I can't justify buying a high quality scope on my SS income.

"Hairlines are microscopic scratches that show up as incuse lines," ← Stated in 3rd paragraph down of following ANACS link.
http://www.anacs.com/(A(2pIs3toOzwE...ticle.aspx?ID=7&AspxAutoDetectCookieSupport=1

ToddB67

 

Good job on doing your homework, but your data is giving this old man a headache. LOL

 

One could nitpick a coin to death.

 

GDJMSP,

Thanks for your last reply, very informative, and I agree that a project to record Coin Hairline and Scratch sizes and features, and to be fair and complete cover all the other types of imperfections you mentioned, it certainly would not fit the description of "practical" in most opinions!

However, In my next paragraph with quotes I was just trying to make the point that in the world of Science there seems to be no limit to the extent people will go to do what hasn't been done before and then get it published in some journal devoted to the intelligentsia. Seems like the results of such a project would be out there in cyberspace somewhere if only the Link creators would modify their program algorithms to focus and respond to search words that best describe the subject and intent of a search statement or query instead of always trying to sell us something, but of course there's no money for them in doing that....hump !

"With the plethora of technical information available on a vast panorama of subjects, I wonder why this has not been done already and at least briefly covered in the Red Books ? "

Re your comment "OR - you could keep it simple, and practical, and simply have someone with the required experience do all of these things in about 5 seconds flat", well since I'm retired on low income, do you think someone with the experience and professional microscopic equipment would do it for me Free ? I doubt it, even if I had a valuable coin that I wanted inspected, which I don't at the moment.

Maybe a browser or member reading this thread will know of a source where I can obtain the desired information for statement #1 in post #1 and will be kind enough to post it in this thread.
You have already answered my statement #2 in your post #8....5x is the answer!

Science is one of my favorite subjects, so I like to save information relative to one of my particular interests in that field for reference when doing study work or to include in a future post.

Kudos to those who like finite detail, otherwise Neil never would have stepped on the surface of the moon and we might never make it to Mars sometime in the future !
BTW, in a previous occupation I had the pleasure of shaking Neil's hand and since he was one of my hero's, I was shaking in my boots at the time ! LOL

ToddB67

 

5 SECS and you can call it AU 55 OR MS65... REALLY..

 

Remember that science is always a work in progress. I spent my career as a research and development scientist, always fusing the lastest science with technology. One thing I learned is that nothing is the end all thing.

 

GDJMSP and wxcoin,

I guess electron microscopes are mostly the venue of biologist and scientists working on the cure for cancer and other diseases and they aren't interested in researching and cataloging coin hairlines and scratches !

BTW wxcoin, since you were/are a scientist, re your avatar you have my respect !

ToddB67

 

SLACKACTION, posted: "5 SECS and you can call it AU 55 OR MS65... REALLY.."

YES, REALLY and actually closer to 3 seconds if the coin is large.

@ToddB67

Hairlines are the easiest type of mark to determine, you'll know one when you see it. From then on the mark becomes a scratch and here many factors determine the degree it affects a coin's surface. These include length, width, depth, and location. All can be described by words as long, deep scratch. Each of us needs to make a subjective judgement of what to call these marks based on our experience. One man's "hairline" is another man's "tiny scratch.

Trying to pin down these marks with measurements is folly because NO ONE is going to adopt it. Want proof? The ANA published a coin grading guide long ago. Many ignored it from the beginning and even more do now! I keep one in my bathroom.

 

AU 55 maybe, AU 58...that would be harder