Japanese Gold Koban Set

lermish

I picked up my first Koban a couple of months ago and loved it even more than I expected. I can't have just one. So I've decided to begin the Koban type set by era. I intend to update this thread as I pick up an example from each era.

In general, I prefer them with chopmarks but will be looking for attractive examples regardless of whether they are chopped or not.

Kyoho 1714-1736 - This is currently being holdered. I expect XF Chopmarked but would not be surprised to see AU.

lermish

Bunsei 1819-1828

The chopmark is dubious on this one, it's a little dot at 10 on the reverse. It looks more like damage or a planchet flaw to me.

LukeMarshall

Awesome Historic Ingots , what generally is the weight and purity of these ?

lermish

@LukeMarshall said:
Awesome Historic Ingots , what generally is the weight and purity of these ?

All over the place. Generally, they became lighter over the years. I believe the range is 18.2 grams to down to 3.33 grams.

Purity on most of the earlier issues was ~86%, the later issues dropped to below 60%.

LukeMarshall

Awesome info, I like the look of them.

The different metal compositions should provide for A varietal of Gold Colour, and toning…

Can’t wait to see the set , sounds like a fun and worthwhile venture to collect!

lermish

Man'en 1860-1867

Very tiny at 3.33g total weight with only 57.4% pure gold. The last issue and so small that it fits into a normal size PCGS slab.

lermish

Tempo 1837-1858

I am still fairly new with Kobans but this is the best looking Tempo I have seen. The cut marks are fine and numerous and look more like the much earlier Keicho issues than most of the other contemporaries I have seen. Weight was at 11.2g but still only gold purity of 56.8%.

lermish

Genbun 1736-1818

These are very tough to find problem free. Despite this being graded AU53 it has two small chopmarks (which I greatly enjoy!) on the reverse. Great original looking surfaces, this koban is 65.3% gold on a weight of 13.1g.

The issues are going to start getting a lot tougher going forward.

lermish

Genroku (1695-1710)

This is one of the two keys to the set. Its issuance marked a severe drop in the gold purity, down to 56.4% from the prior era Keicho's 85.7%. The high silver content gives this coin a warm orange glow. It's very difficult to find these without chopmarks (or at all) but they give the coin some nice character.

Hoei (1710-1714)

This is a semi-key part of the set and is rarely available. The gold purity was raised back to 83.4% but the size of the coin was dropped drastically due to a gold shortage. This is very appealing with a strong strike and hints of rose covering the coin.

Ansei (1859)

Another semi-key date despite its late issuance. This was only a one year issue with 57% gold. Due to very favorable, government mandated exchange rates, cheap Japanese fiat gold was being exported to arbitrage and buy silver. To combat this outflow, the Japanese created this issue with very little gold but the same nominal value of 1 Ryo. This coin had several unfortunate wipes but still has lovely color and excellent detail.

TheGoonies1985

Very interesting pieces thanks for sharing them with us!!! You seem to be making great progress.

abbyme24

I love the rim toning on your Bunsei @lermish . You should post your upgraded Kyoho!

Forgive me for hijacking your thread a bit but I didn't see any general Japanese coin threads. I thought I would share some really nice toned pieces I've come across

abbyme24

The fact that these were pretty low purity for the later issues means that there is a lot of silver in the alloy which brings the potential for amazing rainbow toning that can't happen on most gold issues. Despite the low purity, they still had a very rich gold appearance due to a process called "color washing" or "color dressing". This was a chemical process that removed all of the silver from just the surface of the koban. In the case of the examples above this process wasn't done properly on all of the areas, so you have this really neat mix of deep gold and rainbow tones.

lermish

@abbyme24 said:
I love the rim toning on your Bunsei @lermish . You should post your upgraded Kyoho!

Forgive me for hijacking your thread a bit but I didn't see any general Japanese coin threads. I thought I would share some really nice toned pieces I've come across

Always happy to have more Koban talk. Nice avatar change!

Most recent update is this lovely Kyoho graded AU58. I picked this up from our very own @abbyme24 at the ANA this summer to upgrade my chopmarked example above. This is an original piece with attractive warm gold color and that special hammered gold luster.

golden

I wanted one of those decades ago. Just never got around to purchasing one.

lermish

@golden said:
I wanted one of those decades ago. Just never got around to purchasing one.

The common dates can be very reasonably priced. They really are fantastic and a lot of fun.

@abbyme24 won't advertise herself here but I can! She has a few in inventory and is constantly finding new examples.

https://risingsunrarities.com/collections/gold-kobans-and-obans