Assertion: tin | /r/CapableOf | change to gray form
Facets:
value: slowly
type: MANNER
value: from the white form
type: OTHER
Source sentences:
text: When tin is cooled below 13.2°C, it slowly changes from the white form to the gray form, although the transition is affected by impurities such as zinc or aluminum and can be prevented if small amounts of bismuth or antimony are present.