Checking Pole Marks on Japanese Ko-Nanryo Gin [решено]

Hello.

I ask if any person can validate the pole marks (gokuin) on the images here.  Based on the "jyou" character (also shown) and absence of side filing marks the piece is a Japanese Meiwa Ko-Nanryo Gin.  Size, weight and density seem about right.  But the pole marks seem large.  I have a Shin-Nanryo Gin and the pole marks are much smaller, as seen on other Japanese square coinage such as Ichibu.  There are 10 pole marks on the four edges/sides, all as those pictured below.  When judging size, please note the thickness is 2.5mm.

Details

Height 25.5mm

Width 15.3mm

Thickness 2.5mm

Weight 10.16gm

Density 10.72 gm/cm3

Any comments would be helpful.

I have not handled the old type of this coin in person yet so I can't say much from first hand. But I now a bit more about the bu coins and they come with a big variety in edge reeding (fine/coarse/none) and a plethora of different stamp designs.

If everything else you've stated is correct I would lean on the side of genuine especially if the source is reputable.

If possible I would like to get your permission to use your 常 picture for a type differentiation documentation.

Thank you Idolenz, and yes, you may certainly use my jyou character picture.

Just a short update.

With the help of others at Numista I had this coin posted at zeno.ru.  The moderator there indicated this coin as authentic.