Assertion: magnesium | /r/HasProperty | hard
Facets:
Source sentences:
text: Magnesium in bulk is hard to ignite but pure magnesium wheels can be ignited by a burning tire or by prolonged scraping of the wheel on the road surface following a puncture.
text: Even people taking multivitamins may fall short since magnesium is a large mineral that is hard to fit into a daily multivitamin-mineral supplement.