Question: according to the mohs hardness scale what is the hardness of quartz
[{'answer': '7', 'provenance': [{'wikipedia_id': '20474', 'title': 'Mohs scale of mineral hardness', 'start_paragraph_id': 8, 'start_character': 87, 'end_paragraph_id': 8, 'end_character': 88, 'bleu_score': 1.0, 'section': 'Section::::Minerals.\n'}]}]