Question For "V" Nickel "Experts"

@crazyb0, while I understand what you were hoping to accomplish, I still need to give you a head slap for the use of steel wool on your two coins.

My 1889 V nickel is in pretty poor shape (completely slick on the rev), but does have a pleasant grey color. I'm sure someone more knowledgeable than I am can weigh in on whether the mint had any transient issues with feed stock alloy variation in 1889, but as a n=1, mine seems to be ok.

Dave, I said test, I am a big boy, I know what I am doing! As far as I am concerned these are culls anyway and will be replaced ASAP with a better, natural one if found and the old one scraped unless someone wants a "hole-filler details coin.

In science, a subject must at times be sacrificed to determine the premise!

Dave, LOL, look what we do to clean the ancients! and that isn't called "drastic"!

Thanks Dave, that's kinda what I was asking, I too have other older nickels, Shields to Buffalos that have the dark deal, and as so often are just lumped into the ED category. Where they may well belong, but after playing Garage imp myself over the years, heat does may things to coins other than shrivel like prunes! Darkening through a partial temper is an effect I did on Jeffersons but it is my understanding both process of manufacture and materials were a bit different by then...I no longer can prove that on older coins now by destroying a few Buffs!

Late to the picnic, but must say in 50-odd years of collecting I've certainly seen a lot of dark V-nickels, but certainly that number is in the tiny majority. They seem to occur about as often (proportionately) in the Shield nickel series. Having dug more than a few similar Buffalos, I've always just assumed this darkness was primarily due to ED. Are you suggesting this phenomenon is more frequent in V-nickels?

It is certainly possible that the planchets used for coins struck in 1889 and 1890 were of inferior quality and contained more impurities or contaminants in their alloy. This would explain why it only effects V nickels since they were the only coin using that composition in 1889 excluding the ultra-scarce 1889 3 Cent Nickel piece.

The composition was 75% copper and 25% nickel.

Nickel itself is an interesting and unusual element. Nickel-bearing sulfide minerals such as pyrrhotite and pentlandite (with iron) are often found alongside chalcopyrite (an ore of copper) and stannite (tin ore) as products of the decomposition of cooling sulfide melt deposits, along with stibnite (antimony) and other minerals. The early smelters and refiners discovered nickel mostly by chance mainly because its presence and that of antimony in the mined ore stocks kept frustrating their attempts at smelting good copper.

Joseph Wharton's mine, conveniently in Pennsylvania (now Nickel Mines, PA) was the largest producer of nickel in America (and the only one of any significance) in the latter part of the 19th c.
By the late 1880s, the pyrrhotite ore veins in the Pennsylvania mines had been largely depleted of high grade ore, and the quality of the remaining ore was noticeably poorer and more difficult to extract, with higher proportions of undesirable components such as arsenic and lead making refining and smelting at the New Jersey Wharton furnace a dangerous and increasingly unprofitable challenge.

Since Wharton's mines were the main supplier of the US Mint, and had been since 1865-1866 when he convinced the US (and the world) of the desirability of copper-nickel coinage, it is likely that the Mint would have noticed the increasingly poor quality of the bar stock being purchased for making planchets.

Furthermore, the development of producing nickel mines in South America and the discovery of large workable deposits near Sudbury (Ontario) created supply pressures on the price of Wharton's nickel; by 1893 Wharton's mines were boarded up and mostly backfilled with the tailings. There was additionally a collapse in copper prices in the late 1880s after collusion and price-fixing among firms and traders was broken up, which led to further economic damages since copper was "right there in the mix" with nickel mine output.

I can't prove it but I suspect that the "dark nickel" problem in these years may be related to that same inadequate ore from Wharton's nickel mines and the resulting difficulty in smelting clean ingots and bar stock due to high levels of other sulfide contaminants (e.g. arsenopyrite, nicollite/nickelene) which may have darkened the color of the alloy by their presence.

A metallurgist, chemist, or assayer might be able to contribute more on that subject; you could do XRF or spectroscopy to assay the quality of the alloy used for planchets in those years and differentiate their elemental composition.

You're welcome. I'm no expert, but a hobbyist mineral collector.

Cobaltite (the main ore of cobalt) is reddish-silvery white to gray in color. Cobaltite (and many other pyrites and related minerals) are found with copper and nickel; however, the trademark "cobalt blue" color as used in glassware and ceramics is a blue powder made from combining cobalt + aluminum oxide (alumina) at high temperature and pressures.

(You can make it yourself for use in pottery and ceramic crafts provided you happen to have convenient access to a 1200 degree (Celsius) ceramic pressure sintering setup...gee, who doesn't have one of those in the living room?)

kbbpll, I think you are seeing a "reflection" of the product, if you catch my drift!