Assertion: chestnut's bark | /r/ObjectUse | used in the leather tanning industry
Facets:
value: heavily
type: DEGREE
value: prior to the 20th century
type: TEMPORAL
Source sentences:
text: The bark of chestnut oak has a high tannin content and prior to the 20th century was heavily used in the leather tanning industry, but the wood was usually discarded since it was considered inferior to that of Q. alba.