Miguel del Rio

3 hours ago, VKurtB said:

Like 1953 British uncirculated sets. Yikes!  100% pure “shower curtain” original packaging.

Yes, volatile organic compounds (VOCs) can have an odor.

These are photos of the Chile 1968So coins that were purchased in their PVC flips 50 years later, now holdered:

The damage done to the 5 Peso coin is typical of the packing from the mint and not due to any interaction with the PVC flip.

PVC flips were popular decades ago before anyone knew any better. However, overtime, the damage to coins became apparent.

These Chile 1968So coins were shipped from Santiago and some coins are still sold in their original holders. I was fortune to purchase a set that did not have any signs of damage, however, this set currently for sale on Ebay is not so fortunate. Notice how the 5 Peso coin is discolored where it made contact with the flip:

Photo below shows the upper half of the PVC flip used to ship the Ecuador 2006 coin, now in the square hard plastic capsule, that shows the most significant damage I've encountered thus far (flip labelled 240A):

:

Modern soft plastic flips don't use PVC, however, they are rumored to bleed other damaging chemicals on to coins over time.

See Recognizing Coin Holders That Contain PVC.

The hard plastic Mylar flips and capsules don't outgas harmful chemicals.

12 hours ago, James_OldeTowne said:

Your photos are MUCH better than the originals created by the seller.  I greatly dislike those kinds of photos of white-on-black cameo proofs that display not even a hint of the actual character of the fields.

The photos were obviously the seller's and not taken by The Coinhouse Auctions. 

I had similar experience with a merchant who claimed his picture of a nearly flawless proof was taken years before the coin was damaged by the PVC flip in storage.

These are photos of the actual coin received:

These are the promotional photos:

On the reverse side, notice the toning between the words "25.000" and "SUCRES" and extending to "ECUADOR" matches toning to be found also on the damaged coin's reverse.

The damage is almost entirely due to pitting, the remainder due to foreign matter possibly deposited by the flip as well.

This would lend credence to that merchant's explanation that the coin surfaces decayed due to the flip in which it was stored over time.

21 minutes ago, e1cnr said:

The spots are in the same positions so it is the same coin. It is amazing/deceptive how lighting/overexposure can change our looks of a coin.

Yes.

Some auction houses supply their own photos when the seller's can not be used. This HA auction delayed the photo of this coin while they made suitable reproduction:

https://coins.ha.com/itm/brazil/brazil-republic-gold-proof-discovery-anniversary-20-reais-2000-/a/61181-97118.s

Greetings!

Bought a coin not so recently at Auction No 16 from The Coinhouse Auctions in Belgium on Sept. 30th which Peter Eyckmans so kindly posted on Nov. 4th, and subsequently received the coin Nov. 16th.

Expected a coin resembling this photo posted for lot 574:

Wouldn’t have bid for the coin given its visible imperfections except that this coin is difficult to obtain in higher grades and, at 50 Euros, what could go wrong?

These are photos of the coin actually received:

Notice that some identifying features of the idealized coin are also present in the actual coin.

Coin has the appearance of being sprayed with a corrosive mist, possibly to hide the latent finger prints.

Could the evenness of the pitting of the surfaces of the coin the result of storage in a PVC holder and subsequent removal of the PVC deposits?

The 50 Euros bid price turned in to over $100 once shipped via PayPal and registered mail.

Imagine using an auction house to pawn off junk coins rather than taking the coins to a scrap dealer!

Attentively,

MiguelDelRio

A CoinTalk member asks, "Could it be residue from whatever organic was dissolved and then redeposited if the acetone evaporated without being thoroughly rinsed?"

This is true.

Acetone is such a good organic solvent that pure acetone is only theoretically available in the lab where it's distilled.

It takes additional solvents to remove acetone impurities using a probe sonicator.

Tub style ultrasound is not sufficient since the only solvent that may be used in the tub is distilled water. Use of other solvents present a fire hazard. Also, differences in acoustics could burnout the acoustic generator.

Differences in surface tension among solvents make sonication necessary near the target surface.

"Acetone HPLC Grade" has the least residue at 5 ppm.

Thank you for asking.

On 10/3/2019 at 9:24 AM, Conder101 said:

...If you do anything it would be a soak and then flowing rinse with pure acetone.  Don't rub, don't wipe, don't even try to dry it off.  The acetone will evaporate off the coin in just a few seconds so don't try to hurry it up.

Acetone always leaves an ugly residue, regardless of purity.

Such acetone residue can not be conventionally removed from a coin surface by distilled water or by isopropanol because these solvents bead, while acetone covers the coin surface completely.

For example, an acetone dip may be used in conjunction with other solvents to provide a substrate free from residue.

One would need a ventilator hood, a probe sonication device, a temperature controlled nitrogen evaporator, supply of glass beakers, metal clips to fasten the substrate, etc

Don't know if a coin could be mounted in such a way as to survive the probe sonication which provides up to 1,000 times the power of tub style ultrasound.

See technicians exchange below:

Such a procedure is outlined in the response below: 

These are examples of coins having acetone residue:

Best regards,

The following 23 coins are for sale on Ebay as authentic coins from Peru, however, the Krause-Mishler catalog numbers for these coins indicate that they are exonumia, and as such, were neither solicited nor authorized by Peru:

1) PERU 20 SOLES 1996 PATTERN SILVER PROOF #alb38 361 (Ebay# 273914690286)

Reverse: https://i.imgur.com/GJvUM8h.jpg                       Obverse: https://i.imgur.com/uuAtTvU.jpg

Reference: Exonumia Peru KM# X-14.1
Listing: https://www.ebay.com/itm/PERU-20-SOLES-1996-PATTERN-SILVER-PROOF-alb38-361/273914690286

2) PERU 20 SOLES 1996 PATTERN SILVER PROOF #alb38 087 (Ebay# 283536126782)

Reverse: https://i.imgur.com/qa8tl6r.jpg                            Obverse: https://i.imgur.com/iGDfuW3.jpg

Reference: Exonumia Peru KM# X-13.2
Listing: https://www.ebay.com/itm/PERU-20-SOLES-1996-PATTERN-SILVER-PROOF-alb38-087/283536126782

3) PERU 20 SOLES 1996 PATTERN ALUMINIUM PROOF #alb38 067 (Ebay# 283536124123)

Reverse: https://i.imgur.com/neG6YJI.jpg
Obverse: https://i.imgur.com/bTp1Cm3.jpg
Reference: Exonumia Peru KM# X-22d.1
Listing: https://www.ebay.com/itm/PERU-20-SOLES-1996-PATTERN-ALUMINIUM-PROOF-alb38-067/283536124123

4) PERU 20 SOLES 1996 PATTERN COPPER PROOF #alb38 065 (Ebay# 273914667908)

Reverse: https://i.imgur.com/FbxAdhz.jpg                         Obverse: https://i.imgur.com/RTjB1wM.jpg

Reference: Exonumia Peru KM# X-16e.1
Listing: https://www.ebay.com/itm/PERU-20-SOLES-1996-PATTERN-COPPER-PROOF-alb38-065/273914667908

5) PERU 20 SOLES 1996 PATTERN ALUMINIUM PROOF #alb38 067 (Ebay# 273914667615)

Reverse: https://i.imgur.com/UZNjntL.jpg
Obverse: https://i.imgur.com/hDbv7BM.jpg
Reference: Exonumia Peru KM# X-16d.2
Listing: https://www.ebay.com/itm/PERU-20-SOLES-1996-PATTERN-ALUMINIUM-PROOF-alb38-063/273914667615

6) PERU 20 SOLES 1996 PATTERN ALUMINIUM PROOF #alb38 059 (Ebay# 273914667217)

Reverse: https://i.imgur.com/LoUN2Oh.jpg
Obverse: https://i.imgur.com/6h9ctx9.jpg
Reference: Exonumia Peru KM# X-20d.2
Listing: https://www.ebay.com/itm/PERU-20-SOLES-1996-PATTERN-ALUMINIUM-PROOF-alb38-059/273914667217

7) PERU 20 SOLES 1996 PATTERN ALUMINIUM PROOF #alb38 057 (Ebay# 283536123052)
Reverse: https://i.imgur.com/SiythdH.jpg
Obverse: https://i.imgur.com/kZdgkzH.jpg
Reference: Exonumia Peru KM# X-15d.1
Listing: https://www.ebay.com/itm/PERU-20-SOLES-1996-PATTERN-ALUMINIUM-PROOF-alb38-057/283536123052

8) PERU 20 SOLES 1996 PATTERN ALUMINIUM PROOF #alb38 055 (Ebay# 273914666816)
Reverse: https://i.imgur.com/FY7EXAF.jpg
Obverse: https://i.imgur.com/q6tCEWq.jpg
Reference: Exonumia Peru KM# X-21d.1
Listing: https://www.ebay.com/itm/PERU-20-SOLES-1996-PATTERN-ALUMINIUM-PROOF-alb38-055/273914666816

9) PERU 20 SOLES 1996 PATTERN ALUMINIUM PROOF #alb38 053 ( Ebay# 283536122614)
Reverse: https://i.imgur.com/kymy3nI.jpg
Obverse: https://i.imgur.com/RHCRI0b.jpg
Reference: Exonumia Peru KM# X-19d.2
Listing: https://www.ebay.com/itm/PERU-20-SOLES-1996-PATTERN-ALUMINIUM-PROOF-alb38-053/283536122614

10) PERU 20 SOLES 1996 PATTERN COPPER NICKEL PROOF #alb38 051 (Ebay# 273914666376)

Reverse: https://i.imgur.com/NQ3KeXa.jpg                      Obverse: https://i.imgur.com/Fd0TxGb.jpg
Reference: Exonumia Peru KM# X-20f.2
Listing: https://www.ebay.com/itm/PERU-20-SOLES-1996-PATTERN-COPPER-NICKEL-PROOF-alb38-051/273914666376

11) PERU 20 SOLES 1996 PATTERN ALUMINIUM PROOF #alb38 049 (Ebay# 273914666130)
Reverse: https://i.imgur.com/FrAoa2N.jpg
Obverse: https://i.imgur.com/zVnRZUn.jpg
Reference: Exonumia Peru KM# X-19d.1
Listing: https://www.ebay.com/itm/PERU-20-SOLES-1996-PATTERN-ALUMINIUM-PROOF-alb38-049/273914666130

12) PERU 20 SOLES 1996 PATTERN ALUMINIUM PROOF #alb38 047 (Ebay# 283536121874)
Reverse: https://i.imgur.com/89ebjnJ.jpg
Obverse: https://i.imgur.com/AFGj9NM.jpg
Reference: Exonumia Peru KM# X-14d.1
Listing: https://www.ebay.com/itm/PERU-20-SOLES-1996-PATTERN-ALUMINIUM-PROOF-alb38-047/283536121874

13) PERU 20 SOLES 1996 PATTERN SILVER PROOF #alb38 045 (Ebay# 283536121601)

Reverse: https://i.imgur.com/bCCpssn.jpg                        Obverse: https://i.imgur.com/eF9uZSU.jpg
Reference: Exonumia Peru KM# X-20.1
Listing: https://www.ebay.com/itm/PERU-20-SOLES-1996-PATTERN-SILVER-PROOF-alb38-045/283536121601

14) PERU 20 SOLES 1996 PATTERN ALUMINIUM PROOF #alb38 043 (Ebay #273914665339)
Reverse: https://i.imgur.com/86L63HC.jpg
Obverse: https://i.imgur.com/M4mF7Ng.jpg
Reference: Exonumia Peru KM# X-18d.2
Listing: https://www.ebay.com/itm/PERU-20-SOLES-1996-PATTERN-ALUMINIUM-PROOF-alb38-043/273914665339

15) PERU 20 SOLES 1996 PATTERN ALUMINIUM PROOF #alb38 041 (Ebay# 273914665048)
Reverse: https://i.imgur.com/DFcBiNl.jpg
Obverse: https://i.imgur.com/jUmDO7h.jpg
Reference: Exonumia Peru KM# X-19d.2
Listing: https://www.ebay.com/itm/PERU-20-SOLES-1996-PATTERN-ALUMINIUM-PROOF-alb38-041/273914665048

16) PERU 20 SOLES 1996 PATTERN NICKEL PROOF #alb38 039 (Ebay# 273914664793)

Reverse: https://i.imgur.com/44mBrjb.jpg                         Obverse:  https://i.imgur.com/ws8oaDi.jpg
Reference: Exonumia Peru KM# X-12f.1
Listing: https://www.ebay.com/itm/PERU-20-SOLES-1996-PATTERN-NICKEL-PROOF-alb38-039/273914664793

17) PERU 20 SOLES 1996 PATTERN ALUMINIUM PROOF #alb38 037 (Ebay# 273914664533)

Reverse: https://i.imgur.com/R99KYdL.jpg                       Obverse:  https://i.imgur.com/859OyAG.jpg
Reference: Exonumia Peru KM# X-18d.1
Listing: https://www.ebay.com/itm/PERU-20-SOLES-1996-PATTERN-ALUMINIUM-PROOF-alb38-037/273914664533

18) PERU 20 SOLES 1996 PATTERN BRASS PROOF #alb38 035 (Ebay# 283536120212)

Reverse: https://i.imgur.com/WXy2lxL.jpg                        Obverse:  https://i.imgur.com/V3qyvqv.jpg
Reference: Exonumia Peru KM# X-19a.1
Listing: https://www.ebay.com/itm/PERU-20-SOLES-1996-PATTERN-BRASS-PROOF-alb38-035/283536120212

19) PERU 20 SOLES 1996 PATTERN ALUMINIUM PROOF #alb38 033 (Ebay# 273914664031)

Reverse: https://i.imgur.com/p8f0beC.jpg                         Obverse: https://i.imgur.com/Fn6BYCj.jpg
Reference: Exonumia Peru KM# X-11d.2
Listing: https://www.ebay.com/itm/PERU-20-SOLES-1996-PATTERN-ALUMINIUM-PROOF-alb38-033/273914664031

20) PERU 20 SOLES 1996 PATTERN ALUMINIUM PROOF #alb38 031 (Ebay# 273914663810)
Reverse: https://i.imgur.com/KCCfP6u.jpg
Obverse: https://i.imgur.com/XQKaNNk.jpg
Reference: Exonumia Peru KM# X-17d.2
Listing: https://www.ebay.com/itm/PERU-20-SOLES-1996-PATTERN-ALUMINIUM-PROOF-alb38-031/273914663810

21) PERU 20 SOLES 1996 PATTERN ALUMINIUM PROOF #alb38 029 (Ebay# 273914663547)
Reverse: https://i.imgur.com/QDeBxkz.jpg
Obverse: https://i.imgur.com/0oAEkcG.jpg
Reference: Exonumia Peru KM# X-17d.2
Listing: https://www.ebay.com/itm/PERU-20-SOLES-1996-PATTERN-ALUMINIUM-PROOF-alb38-029/273914663547

22) PERU 20 SOLES 1996 PATTERN ALUMINIUM PROOF #alb38 027 (Ebay# 283536119242)
Reverse: https://i.imgur.com/W0NtMFI.jpg
Obverse: https://i.imgur.com/Kv4S5AB.jpg
Reference: Exonumia Peru KM# X-17d.1
Listing: https://www.ebay.com/itm/PERU-20-SOLES-1996-PATTERN-ALUMINIUM-PROOF-alb38-027/283536119242

23) PERU 20 SOLES 1996 PATTERN ALUMINIUM PROOF #alb38 025 (Ebay# 283536118987)
Reverse: https://i.imgur.com/m3aUqlx.jpg
Obverse: https://i.imgur.com/BGH0Ucl.jpg
Reference: Exonumia Peru KM# X-17d.1
Listing: https://www.ebay.com/itm/PERU-20-SOLES-1996-PATTERN-ALUMINIUM-PROOF-alb38-025/283536118987

The catalog numbers for these coins are found at https://www.ngccoin.com/price-guide/world/search/4/?keywords=PERU||1996||20+Nuevos+Soles|PERU++1996+20+Nuevos+Soles

These coins were stored in the vaults of a defunct mint: “In the 1990's a firm in London named the International Currency Bureau, Ltd, commonly known as ICB, attempted to win contracts to issue coins for various third world nations.  They would design and strike a limited number of pattern coins for each country in hopes of winning a contract.  Though many of their issues were attractive, they were unable to win any major contracts.  After a few years they went bankrupt and were liquidated.”

Last year, Paolo_23 asked, "Hello, they are tests that never circulated. Do you still have them?"

With an embarrassment of "rare", magnificent coins readily available, how does one find the time to collect such misattributed coins?

Best regards

On 7/22/2018 at 12:18 AM, Paolo_23 said:

Hello, they are tests that never circulated. Do you still have them?

With an over-abundance of beautiful, "rare" coins, how do you find the time?

16 hours ago, Coin Cave said:

Can I substitute the isopropyl alcohol with Everclear?  They sell 99.9% isopropyl alcohol at electronic stores.  I like it for cutting through cellophane residue.   

I have a number of unused 99+ isopropyl alcohol bottles which leave residue on coins.

Walmart's Equate first-aid brand is 91% isopropyl alcohol and 9% distilled water. It's inexpensive and leaves no residue. Not my first test of this brand, though you can never be too sure. Tested this coin using only the Equate alcohol and no distilled water rinse to see if evaporating the alcohol would leave a residue:

Splashed both sides of the coin with alcohol. Dried the coin. No detectable difference from these images taken afterward:

Used a manual drying bulb rather than the pressurized air since the cans of air can leave moisture on the coin in the form of ice which takes even longer to evaporate:

Placed the coin in a hard plastic basket (used for the ultrasonic cleaner):

Dried one side of the coin, then slid the backside of a clean coin flip underneath the coin. Firmly grasped the coin with the coin flip. Removed the coin, then dried the sink and basket with a cloth towel. Replaced the reverse side of the coin facing up in the basket. Gently shook and tilted basket with coin to remove most of the remaining isopropanol. Continued to dry the other coin surface and the basket. 

What appeared to be specs of debris on the coin were actually microscopic bubbles of alcohol which had not yet evaporated.

Repeated a few times until the coin was dry.

Edge of the coin was still a little wet.

Left coin to completely air dry while setting up camera for photos. (if coin is not completely dry, the alcohol will turn the capsule permanently cloudy).

Setup DLSR camera to take closeup images (entry level model cost me $399.99 with accessories). Set image stabilization, auto white balance, auto focus. Used circular polarizer and set light meter to +1 f-stop.

Took pictures under a variety of lighting conditions, occasionally dusting the coin with the bulb.

Photos shown are 1/16th the square area of the originals.

On 5/26/2019 at 5:08 PM, ldhair said:

There will be no issue with residue if you use acetone properly. If you don't know what you are doing, yes, you will leave residue. 

Further investigation reveals that residue is an issue regardless of the grade of acetone. Maximum non-dissolved solids after evaporation for the highest grade is 5 ppm. The next lower grade, an ACS grade reagent, is 0.001%, or 10 ppm:

Clearly, a procedure involving a successive series of diluting solvents and powerful mixing is required if acetone is to be used. 

Such a procedure is outlined in the response below: 

(In the example above, substrates are suspended in racks on metal clips.)

To accommodate acetone, one would need a ventilator hood, a probe sonication device, a temperature controlled nitrogen evaporator, supply of glass beakers, etc.

The "20 seconds sonication" for each step may require termination upon discovery of solid debris so that the solvent can be refreshed and the coin remain unabraded. Then, the sonication may resume.

A probe sonication device provides about 1,000 times more power than a tub style ultrasonic cleaner, rendering surface tension moot.

On 5/26/2019 at 5:08 PM, ldhair said:

There will be no issue with residue if you use acetone properly. If you don't know what you are doing, yes, you will leave residue. 

Please enlighten us as to the proper use acetone on coins without using a final rinse of distilled water.

Include photos of this procedure, if possible.

On 5/25/2019 at 9:27 PM, rrantique said:

 The boiling point of acetone is 132.8 degrees fahrenheit. Most rubbing alcohol is made out of isopropyl alcohol or ethyl alcohol. Both evaporate at about the same temperature at 180 degrees fahrenheit.

 

P.S. Miguel do what ever you want with your coins.  I was just showing that Acetone will evaporate quicker (ie lower boiling point than Isopropyl alcohol).

Acetone will completely cover the coin surfaces. Much more acetone must be evaporated than water or alcohol, which bead and slide-off the coin.

Residue is also an issue, whether the residue is in solution with the acetone as an impurity or the additional residue dissolves from organic debris on the coin as the solution evaporates.

Distilled water leaves no residue.

14 hours ago, Conder101 said:

Don't be confused by that "Total newbie" label, I know what I am talking about. (I do have a degree in chemistry)  At room temperature without added heat and in still air acetone evaporates roughly twice as fast as isopropanol.  With a little heat or moving air the evaporation rate of acetone is nearly 5 times as fast.  And acetone and water mix completely and easily, and they stay mixed in solution, they do not separate.  Ethanol and Isopropanol do as well.  That is why it is very hard to get any of them to a purity greater than 95%, they will absorb water vapor directly from the air.

I can see that you have never tried mixing these solvents on the surface of a coin.

Low surface tension of acetone prevents the mixing with water on the coin surface.

Acetone forms an even layer covering the coin surfaces, while water beads, rendering water effectively immiscible with acetone on the surface of the coin for human life spans.

See http://ptfaculty.gordonstate.edu/lgoodroad/SUMMER 2011/Chem 1212/chem 1212 chapter 11 solutions[1].pdf

Isopropyl alcohol and distilled water bead and slide off the coin surfaces, leaving far less of these solvents to evaporate as compared to acetone. 

The residue left behind from acetone and isopropanol is also an issue, regardless of the the source of the residue, whether the residue is already present in solution or whether the solvent dissolves any additional residue from organic debris on the coin surfaces.

Evaporating distilled water from the coin surfaces leaves no residue.

I got a thumb print on this coin as it fell from my fingers on to the linoleum floor:

I quickly doused the coin in acetone. I knew the evaporation rate of acetone was far less than isopropyl alcohol, but I still waited for a few moments anyway. Finally, I splashed the coin with isopropyl alcohol, then, using Butyl II gloves to protect by hands while manipulating the coin, I placed the coin into another glass bowl having distilled water. I saw that the coin still had a slick acetone residue, so I repeated a couple of times more, first dousing and soaking the coin in fresh isopropyl alcohol, then rinsing the coin in a bowl with clean distilled water.

Little did I realized that I was not finished, as this photograph shows.

The Butyl II gloves are still tacky. They protected my hands, though not without transferring residue to the coin.

3 hours ago, rrantique said:

Chemicals with evaporation rate of 3.0 (three time the evaporation of normal butyl acetate), such as acetone (5.6), hexane (8.3), or methyl ethyl ketone or MEK (3.8) are classified as 'fast evaporating.'

That may be, however, I haven't had the time to waist for acetone to slowly evaporate and to see how much residue the acetone solution leaves on a coin. (In the time it takes for the acetone to evaporate, more surface residue may be dissolved into the acetone solution.)

11 hours ago, Conder101 said:

Acetone evaporates VERY quickly, and water and acetone are 100% miscible.  In chem labs acetone is commonly used to dry the glassware after washing  because the water instantly is absorbed into it and dispersed and then carried off as the acetone rapidly evaporates.  Very useful for drying flasks and other glass equipment that have narrow or constricted openings that would take a long time to air dry.

Hi Total Newbie, No, you have acetone confused with alcohol. Acetone is volatile, however, it evaporates very slowly. Isopropyl alcohol, which evaporates very quickly and is used as a drying agent, is miscible in both acetone and distilled water. Acetone and water don't mix well, similar to gasoline and water.

4 hours ago, CRAWTOMATIC said:

I dropped the idea of submersive ultrasonic cleaners due to the agitation involved.  I'd imagine it would cause friction/rub/etc....

Yes, if you were to leave the ultrasonic cleaner unattended, you could do damage that may appear only on a high resolution photograph. Ultrasonic cleaners are commonly used to clean jewelry, though for proof coins, I use the cleaner for only a few seconds initially depending on the debris to be removed. Usually, filmy haze is completely dissolved in isopropyl alcohol, so the only consideration is possible debris and suspended dust.

Often, some organic material and debris on a coin is not sufficient to result in a drop in grade, so you will have to remove the film yourself if appearance can be improved.

With the ultrasonic cleaner turned on, you can suspend the coin using silicone tipped tweezers or forceps, though the coin must not have any isopropyl alcohol on it at this stage. I scratched a coin with the tip of otherwise silicone coated tweezers once, so I was motivated to determine that the hard plastic coated basket of the ultrasonic cleaner is not capable of scratching the coin while the cleaner agitates. If you do see a faint outline of the basket left on the coin, it is due to suspended solids or dust while the cleaner was left unattended.

I use a clean, dust free coin flip to maneuver the coin into the basket sitting in a clean sink. If the coin is in a capsule, I expose one surface of the capsule, place the basket on top my hand holding the capsule, then carefully turn the basket and coin right side up. I apply the isopropyl alcohol liberally to the surface of the coin. I place the basket in the ultrasonic cleaner filled with distilled water. Agitate the coin for a few seconds. Remove the basket and dump the water. Dry the sink with a cloth followed by a lint free cloth. Place the basket in the sink. Air dry the surface coin and the basket with a manual pneumatic bulb. Use the outsides of a clean flip to slide underneath and firmly grasp the coin and remove the coin from basket. Use a cloth and then a lint free cloth in succession to dry off the basket. Use a cloth and then a lint free cloth in succession to dry the sink. Place the reverse of the coin back in the basket and repeat until thoroughly dry. Once thoroughly dry, return the coin to a clean flip or capsule.

Repeat process if photos still reveal debris. Place reverse side of coin upright in basket, if necessary. Use longer time setting on ultrasonic cleaner if necessary and prudent.

When taking photos, use a number of light sources since what initially appears to be debris may actually be defects in the mirrored surface of the coin.

This is an example of a slightly fragmented mirrored coin surface that would be a mistake to restore:

This is an example of debris and an organic film on a coin:

I discontinued with the ultrasonic process once I left a scratch with the tip of aforementioned tweezers (upward from left tail feathers):

One of the global publications' weaknesses it that it is impossible to contact a specific contributor to correct a catalog coin specification, to report a coin variety, to report a fantasy issue, or to add a coin.

The online publications are better with corrections, though they are more incomplete than the traditional guides.

In many instances, the traditional guides are the only source for the online publications.

Acetone does not evaporate very quickly. Acetone and distilled water don't mix. You could use isopropyl alcohol to rinse the acetone, and then use distilled water to rinse the isopropyl alcohol. Care must be taken to use an isopropyl alcohol that does not leave a residue. I use Walmart's 91% solution with 9% distilled water, then place the coin in an ultrasonic cleaner. Replace the distilled water solution immediately if you notice debris in the solution as solid debris or suspended dust may scratch the coin while the ultrasonic cleaner agitates. 

You will find an ultrasonic cleaner at Home Depot for under $40. 

If you use chemical gloves to protect your hands from the acetone, residue will be transferred to the coin if you handle it. 

Always photograph your restored coins before sending them for grading since any residue may only appear with high definition photos.

Repeat while residue still appears on the coin.

Take pictures before you attempt any restoration to make sure that any residue detected was not already present.

(I highly recommend the NCS Conservation service.)

The same variation can be found in the Paraguay 150 Guaranies KM# 37 1973 Proof.

This is a photo of the large purity:

This is a photo showing a half size purity typeface:

This is a photo of the official obverse of the 1973 150 Guaranies coins:

This is a photo of the Paraguay 150 Guaranies KM# 37 1973 Proof from the web page portalguarani.com/detalles_museos_otras_obras.php?id=17&id_obras=937&id_otras=155:

Bought this Mixteca Culture coin recently from MA-SHOPs:

It has the same large 1000 fineness stamped between the denomination characters as does the Paraguay 150 Guaranies KM# 36 1972 Proof.

However, another example from NumisMaster shows a much smaller fineness between the denomination characters for the coin:

Other than paying the variant fee, is there an actual advantage to creating a slab which documents the variant when the variant is so plainly visible and the normal coin so well documented?

Thanks.

No getting around the fact that these are "genuine fakes."

I would not want to be caught in Peru with them, especially the one coin having the Peruvian Coat of Arms!

These pattern coins were neither solicited nor authorized by Peru: