Childhood gift - Can Akoyas be this small?

[Herboriste]

Hello,

I already posted in the Mikado Pearls thread.
I received this chain and pendant at birth, some 33 years ago. All I know is that they were bought in Japan and the pearls on the pendant are cultured. It makes them either Fresh Water or Akoya. However, I wonder whether Akoyas can be as small as 4 mm (which is the size of the pearls on the pendant)?
In the pictures, the earrings are unrelated; I bought them yesterday in order to compose a gift set. They are 6 mm and absolutely Fresh Water. The chain and pendant body are sterling silver. The brand is Mikado Pearls, in Japan, but nothing is to be found on this company....

I'll attempt at posting the pictures:













I hope they come out fine.
Thanks to anyone with an idea about these pearls...

 

[jshepherd]

They certainly look like akoya pearls, and yes, they can be that small. This is a strand of 4.5 mm pearls that my wife wears on a regular basis. I agree on the earrings.

 

[Lagoon Island Pearls]

Biwa, perhaps?

 

[jshepherd]

Biwa, perhaps?

Not in the pendant. The earrings are freshwater, but Chinese.