Bust of a Lady

I am currently researching this Bust and would appreciate any feedback or direction.

Providence - This came from an Estate in England recently belonging to the owners 3 or 4 th Great Grandmother. To me this indicates circa American Civil War of shortly after. I have verified this is not Harriet Tugman through her biographer. Because it comes from England it is a puzzel.

Material - Earthenware - which brings me to Eastern Seaboard of the United States. Europe at the time had more fine porciline and bone china. I have researched the hallmark extensively to no avail.

Size Approx: 12 - 14 inches high , 7-8 inches wide and 4 -6 inched deep.

Hallmark H in triangle as shown - I believe number could be as per catalogue or date. On bck of bust. Bottom has no markings o paint just earthenware. 

It is a very interesting piece. I thank you in advance for any direction you could provide.

Good