Mr T

I've found no one reference book is perfect which is why I have more than a shelf of books on various coins. Invariably only a few get used. The Internet should make this easier but I think it's the same problem as the various reference books - everyone has a different opinion.

I think vinegar will shift verdigris but you need patience. Anyway, good to see you sorted it out.

Some really high-quality Australian fakes have appeared recently - genuinely look like the real thing but what gave them away was the same die markers on multiple different coins. It's worrying.

I assume the alloy was close enough - it looks like the fakes were of moderate quality (produced with dies at least) so they may have gone to the effort of using gold from common-date sovereigns, though I didn't think the 1928SA sovereign was terribly rare or expensive. I don't think it would have been fraudulently obtained gold (but anything is possible). Not sure whether the coins in question were just meant to be an easy means of exchanging value or to deceive a collector though - they do look fake but it's not a rare coin I believe.

Unusual indeed for it to have passed quality control. Hard to say what it is but maybe some sort of lamination fault? I get the impression that circulating errors end up being worth more than mint set errors.

Most likely due to unscrupulous mint workers in the late 1970s. The 2000 $1/10c mule (and similarly the New Zealand 2004 10c/$1 mule) is something you do have a chance of finding though.

I believe the planchets were dipped in acid to remove some of the copper from the surface.

Sorry to drag it up but I acquired a 1902 crown the other day which did have a few green spots, but nothing that had fully taken root. I agree that verdigris on sterling silver coins is unusual (I couldn't recall any examples barring my recent purchase) and probably would be due to contact with other infected coins rather than environmental factors.

It is an absolute stunner - almost perfect strike on that obverse.

Alright thanks for clearing that up - haven't got to looking at the early Victorian stuff yet though.

Hm, I haven't heard of that one (not that I follow it too closely) but there was an article in the Australasian Coin and Banknote Magazine about predecimal doubled dies recently and I don't think it got a mention. Might need to dig out the article again...

I still haven't looked through my Rennick's error coins but I always got the impression the author was very much into the predecimal side of things and any information about decimals was what was provided to him. Possibly part of the problem is that there are probably quite a few predecimal doubled dies that get mislabeled as re-engraved dates.

I've been looking in a few places trying to work out what the edges were on crowns from 1821 onwards but can't quite seem to get it. It looks like there were reeded edges with no inscriptions in many years but what is unclear is if the various years with edge inscriptions had reeded edges or not (in the back of my mind some did but I'm sure some didn't too). Anyone know which edge inscribed years had reeded edges too? I'm mostly interested in 1887 onwards but I'm curious about the George IV crowns too.

It seems to me that the predecimal doubled dies are much more popular than the decimal double dies (I guess they probably happen more frequently in modern production). I'm not too into the errors myself but things like upsets, clips and partial collars are the things that seem to sell for any reasonable amount above face value.

Weren't their later coins made to order? I got a 1982 or 1983 set not long ago that came with a pamphlet about ordering which suggested they would make as many as they got order for (and I guess would explain the non-round numbers produced).

Looks like it could be struck out of collar? Not sure how popular error coins are in the UK but here in Australia you could sell it for tens of dollars at least. Nice find anyway - normally the mint should pick this up, or at worst a security company's rolling machine should reject it - they don't often get to circulation.

Probably not - a couple of years ago I got a bunch of site hits (from which country I no longer remember) but they had spoofed some field or other (browser language I think?) to be "VOTE TRUMP" - possibly something similar. Occasionally I see fake hits that just spam the referrer field with some site they're trying to advertise - again, possibly something similar.

Yes it looks to run under the letters - struck through wire?

The Uniform Coinage of India 1835 to 1947 by Stevens and Weir is a good reference - it says that 24,144,000 1947 Bombay 1/2 annas were minted but gives it an equivalent value to the Calcutta. The David Fore Collection of British Indian coins (which was very comprehensive and was sold by Baldwins) didn't seem to have an example though (at least not in the sequence of regular coins). I wouldn't be surprised if a lot were made and subsequently withdrawn (or perhaps never even issued).

Very nice! Are those pages PVC though?

We'll see - in Australia they did a letter for each $1 for a few years (I think they may have stopped) - none circulated and they did each letter each year for a couple of years.

Thanks. Looks like it's missing the 1863 die number 5 penny.

Maybe - I wouldn't be surprised if there are more varieties these days, though I expect a lot would be such small changes that you couldn't spot them with the naked eye as they don't hand make dies any more. They could probably easily reduce the profile by 10% without anyone noticing and strike a whole lot more coins.

I'll make a note of it.

Even in Australia there are a lot of decimal varieties (particularly after the introduction of the Ian Rank-Broadley obverse). I suppose modern mints are just as interested in extending die life as the mints of last century.