例句與造句

1. A quartz vein included within the Mary Ellen stock carries visible gold, and a quartz stringer within sheared metaleucodacite porphyry dike contained disseminated arsenopyrite, and showed 0.01 oz / ton gold along with 0.01 oz / ton silver.
2. It's difficult to find quartz stringer in a sentence. 用quartz stringer造句挺難的