What do you call these lines?

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Looks like die polish to me they are all consistandly angled and even between the denticals... I don't think you can get that consistant on a wizzed coin...

 

Die polish abrasions. Not random enough for cleaning or scratches or a worn die. Radial flow lines would not not have such a shallow angle as they are basically the luster, which can be seen as the cartwheel effect on certain coins, and flow from the outside to the centre as the metal moves to fill the dies for the devices.

 

I guess the lines are part of the design

aah those lines… die polish +1

 

Looks like one of the Trade Dollars struck in India under British rule; they were struck on screw presses and there was a bit of twisting in the process which caused these "drag marks," I think, so I went with "radials" which seems closest to me.

 

It looks like you have nothing to do

 

Thanks, I enjoy these

 

Those are unpolished, lapped areas of the original die surface.

 

I don't think it has anything to do with polishing. To me, coins with this less desirable. I'm assuming it is on a cupronickel coin.

Radials isn't a term I would use but it appears to be the answer here. Certainly doesn't appear to go through the devices, so maybe it has something to do with grinding the die down in production? As in the design is punched into the die after the radial lines are already present.

 

What you are trying o explain is lathe lines, They are usually polished/removed from the die surface before strike.

 

It does look like a British Trade Dollar and I think your explanation makes the most sense.
More people are going with die polish but those seem to look different from the coins I've observed (not like what I'm seeing in this picture).

 

ksparrow, posted: "Looks like one of the Trade Dollars struck in India under British rule; they were struck on screw presses and there was a bit of twisting in the process which caused these "drag marks," I think, so I went with "radials" which seems closest to me."

This is what radial die erosion looks like.

When I thought this was "common knowledge," I posted this quiz last year on another site and I was shocked that not even professionals dealing in foreign coins knew what caused the flow lines to look as this. Most thought it was the way the dies were polished. Apparently, this characteristic has been left out of virtually every publication for decades. The Indian Mints were given these old presses from England and continued to use them into the 20th Century. This $T was struck at Bombay.

This is what normal radials look like on a coin struck on a more modern press as the die gets very worn:

 

Thanks @Insider - another intriguing post and some good info for me. I think I have a couple like this, somewhere.

 

@Insider I can't speak for anyone else but I think these are great learning exercises. I have been collecting less than two years so the more I can learn with these visual aids the better

 

I guess I had a good buzz last night. those lines look nothing like what I thought I saw. Wow was I off.

 

I am not disputing this claim nor what @Insider had to say about it, just discussing it and speculating upon the mechanics causing the result.

My initial reaction was that the lines looked like the radials seen from die wear but the circular nature told me it couldn't be so because everything I have read about the early US screw presses states that the hammer die is mounted such that it stays rotationally stationary in relation to the anvil die. I imagine that the interface between the screw and the hammer die housing is lubricated regularly and though I have never seen drawings showing it, I also imagine that there is a register mechanism that keeps the anvil die housing from rotating, such as a guide on the frame or register pins between the anvil die housing and the hammer die housing. If the register mechanism was worn, it would allow the anvil die housing to rotate to the limits of wear when the screw applied pressure to the housing.

I don't recall ever seeing these rotational marks on any US coinage struck from screw presses, although I don't pretend to have seen tens of thousands of screw press-struck coins. So, the theory being presented here is that the screw presses gifted to India were worn out, particularly in the register mechanism, and the authorities just didn't have the resources or care enough about quality to repair the presses.

Anybody care to correct or amplify upon my speculations?

Interesting post and new knowledge gained. Thanks!

 

I knew exactly what these were, so I called them "die wear." I've never hear the term "radials" used before other than tires. "Spiral flow lines" would be how I'd describe it more precisely. The denticles of fake British Trade Dollars don't get these right. The London issues (1925 and 1930) won't show these.

 

When in doubt, the vernacular is "anomaly." An anomaly isn't anything, but it covers everything.

 

Weren't worn out when gifted, else you would see this effect on British coinage also.

Back to your statement "If the register mechanism was worn, it would allow the anvil die housing to rotate to the limits of wear when the screw applied pressure to the housing. " I would expect to see some shearing/mechanical doubling of the design devices.