How could luster be quantified?

dan1ecu

We hear of "subdued" luster, "blazing" luster, "booming" luster, "satin" luster...

Experienced collectors can picture in our minds what a coin that is described as one of the above looks like. I wonder if there would be a way to assign a number to a coin, which would serve to quantify its luster. Perhaps there's some testing method that would allow this? I mean a simple testing method that wouldn't involve using expensive instruments.

Have you ever though about how this could be done?

Dan

morganbarber

It would be done the same way we have been quantifying eye-appeal for years. .................................
What?, we haven't been?
nevermind

Coinosaurus

It seems that one *should* be able to quantify lustre and reflectivity with the right instruments. I'm sure there are folks trying to do this, and the services have probably dropped their share of dough into this problem.

Yes, grading is ultimately subjective, but I think some parts of grading should NOT be subjective. How far can a PL coin reflect images, for example. Computers can measure these things much more consistently than humans.

stev32k

I feel pretty sure an instrument could be developed that could measure luster if there was enough of an economic incentive. The development costs would be high and I doubt the market is large enough to recover the initial expense. Outside of the major grading services the ANA and maybe two or three other organizations would be the only potential buyers. Maybe one or two of the largest dealers might buy such an instrument, but the cost for each unit would be prohibitive for most.

LucyBop

Very diffulcult as it is a subjective opinion, just as is a numerical grade...


What is strong luster to me, may not be to you and vice versa..

mozin

Don't think it will happen. Prooflike and Deep Prooflike is sooo much better than ordinary MS luster.

roadrunner

There is nothing like the thrill of a swirling carthwheel with no breaks booming through original patina. I prefer my coins non-PL so I can see every bit of swirl. If I wanted PL or DPL I'd buy proofs.

roadrunner

sumnom

There is too much talk about grades as it is.

MrEureka

There is too much talk about grades as it is.

True. Then again, effective computer grading would ultimately diminish the need to "talk about grades".

airplanenut

<< <i>True. Then again, effective computer grading would ultimately diminish the need to "talk about grades". >>

Then we discuss Mac or PC

I agree with some others that you could probably find an instrument and set up a scale to measure lustre. However, I don't really think it to be necessary, as most coins are pretty obvious under a light. I could go to someone who's never seen coins outside of pocket change, and he'll agree that one of my 1881-S' or my 1880-S is a blazer compared to an 1885-O morgan. Not to say that the 85-O isn't very, very lustrous, just not as lustrous. The 80-S and 81-S would be at the top of the scale, and the 85-O between the middle and top...

Jeremy

cladking

Luster shouldn't be much of a problem for optical grading except where toning
interferes with it. Luster has texture, brightness, reflectivity, and evenness. It
also has depth which would likely be more difficult to quantify.

While most of what people refer to as "eye appeal" is measureable with cur-
rent technology, there are parts of it which won't really be quantifiable for
years by machine. The same likely to luster.

LincolnCentMan

I can see it now:

Condition: 1-70 scale
Color: 1-10 scale
Luster: 1-7 scale
Strike: 1-5 scale
Contrast: CAM/DCAM
Mirrors: PL/DMPL
Nice for the grade: star

So my 81-S morgan is a MS64,1,7,5, DMPL obverse, PL reverse, DCAM *

I wonder how the price guides will list that one.

David

airplanenut

<< <i>So my 81-S morgan is a MS64,1,7,5, DMPL obverse, PL reverse, DCAM * >>

PL/DMPL coins have less lustre... they have mirrors, instead. So your coin wouldn't exist.

cladking

<< <i>I can see it now:

Condition: 1-70 scale
Color: 1-10 scale
Luster: 1-7 scale
Strike: 1-5 scale
Contrast: CAM/DCAM
Mirrors: PL/DMPL
Nice for the grade: star

So my 81-S morgan is a MS64,1,7,5, DMPL obverse, PL reverse, DCAM *

I wonder how the price guides will list that one.

David >>



This is exactly why collectors don't like grading and instead have coins priced. The
problem is that the spread between grades has grown so large that it has become
difficult to price unc coins on a ten point scale. Even if more points were used, there
would still be market variation in pricing simply becauuse it is individuals who purchase
coins and individuals have their own preferences for strike, luster, marking etc.

Price guides would be much more complicated if coins were graded but at least the grade
would tell you about the coins condition.

It would be possible to use both systems until price guides were fine tuned a little. In the
long run many coins' prices could be much more accurately determined by the grade if such
a system were in use. The prices of rare and seldom seen coins will always be a little more
difficult to pin down and this will certainly apply to the anomalies like superb gems with a
little rub or poorly made junk which has no marking at all.

sinin1

I think it could be quantified


have you ever looked at your coins under 40-60 x (dissecting microscope) ?



luster is equated to depth and frequency of flow lines inthe field


and then how much of the devices and letterings/mottos show flow lines




I think some fancy equipment could quantify these things

roadrunner

This would work great for brilliant Morgan dollars and $20 Saints for example. But it would be a disaster for mid and early 19th century type. Everyone would find out that all their UNC coins are not actually unc....at least all those below about MS63-64. The TPG's going for this would be similar to the Auto makers & Oil companies voting for electric cars....not gonna happen anytime soon.

roadrunner