AWAJI / MINPEI YAKI (淡路民平焼)

http://www.tklibby.com/Awaji_Pottery.html

http://www.gotheborg.com/marks/awaji.shtml

Otagiri Mercantile Company OMC

The This company was in business from 1954-1994. It was bought out by Enesco in 1994. Registered in NYC and San Francisco. Recognized by its gold diamond shaped sticker  with OMC.

Otagiri imported wares from many Japanese kilns/companies. Most were marked with an OMC sticker. However some were produced especially for Otagiri and have an incised mark or a transfer mark with Otagiri. These appear to have been made around the mid 1970's to mid 1980's. 

Imports from Japanese Kilns/companies include:

Kozangama (Mino)

  

UPDATE:

SEIZAN GAMA 

***There is uncertainty even among Japanese sites as to the reading. 

From comparison of the bone script characters, I am going with Seizan for this and another similar mark.

*These are similar but not exact. Both appear to be Sei in bone script, although on many Japanese sites the mark on the left uses the Ken reading. 

 Gold Imari (Nagoya)

Meito 明陶

Kutani 九谷

Seihogama 正峰窯

Soma Ware

Tetsusaburo Gama 哲三郎窯 (ARITA)

Touhou

Shibata Toki 柴田陶器 

The Handcrafted Otagiri Original sticker/mark file date Dec 5, 1977~

Incised and transfer marks