Meiji and Ansei, how to know the difference [επιλυμένο]

Hello experts

I am not familiar with the Japanese language, and unable to identify the differences between these two coins:

Ansei Era:

N#55953

Meiji Era:

N#182974

Could someone indicate the key feature that should be examined in order to distinguish between coins from these two eras?

Thank you for any comment

Geison

Shortly, they have the same script. So,  they are the “same”

Identifying the year depends only on the handwriting of each, because both have the same characters.

But they have difference in their composition. Ansei is 87,3% silver

Meiji is 80,7% silver

But, when we talk about the kanjis. What i saw is in the Kanji 常(Jo), im no expert either.

In Meiji the three upper strokes should be straight and parallel, and in the Ansei should be curved and angled.

I think this can help.

https://antylink.jp/report/24394

Here’s a topic about how to distinguish them, it has to do with the positions of the inverted sakura:

https://en.numista.com/forum/topic173491.html 

1 Bu ID chart and extra info in Hartill:

Thank you guys
All information very helpful!