This is an  early to mid 1800's lignum vitae snuff mortar and pestle . It was used to grind snuff from the tobacco leaves..This example has some ring turned decoration on the base of the mortar. Good colour and patination.

The mortar measures 8.6cm h x 4cm w at the top.

Antique Treen Snuff Mortar & Pestle - lignum vitae