Mike welcome to the board. I don't know where you are from...U.S., Europe, etc. but if its U.S. then I believe you have a Tiffin Carrara Jade #17179 low footed comport. The Carrara line was produced from the early to mid-20s, only a few years & is known for at times exhibiting black streaks which evidently was caused by a batch overheating. Carrara was produced in several colors, Coral (orange) Jade (green) Pearl Blue (pale blue) & a Lavendar (light purple) although the Lavendar is very uncommon. Sound dumb I know, but was made to designed/produced to resemble pottery. I have seen more than a few Carrara Jade pieces that exhibit the black streaks like yours & attached is a one I had years ago. Ken