Glass ink holders are the best way to store inks, especially iron gall blends. These screw top glass holders are water tight, and hold .16 oz (5 ml) of ink or gouache, and 4 are included.  They are the perfect size to dip calligraphy pens or small paint brushes. 
The Spalted Tamarind holder is hand-cut, sanded, and coated with a satin varnish. Tamarind is a tropical wood, mostly grown in Africa, with pale yellow sapwood. The 'spalting' or discoloration is very common in sapwood, and accounts for the majority of the wood imported into the U.S.
The piece measures 6" x 2' x 1" high.