( ( In ( addition ( to ( the quartz ) ) ) ) ( , ( ( several ( other minerals ) ) ( ( have ( produced ( attractive specimens ) ) ) . ) ) ) )
(ROOT (S (PP (IN In) (NP (NP (NN addition)) (PP (TO to) (NP (DT the) (NN quartz))))) (, ,) (NP (JJ several) (JJ other) (NNS minerals)) (VP (VBP have) (VP (VBN produced) (NP (JJ attractive) (NNS specimens)))) (. .)))
In addition to the quartz, several other minerals have produced attractive specimens.
(ROOT (S (NP (DT The) (NN mineral) (NN quartz)) (VP (VBZ is) (VP (VBN used) (S (VP (TO to) (VP (VB produce) (NP (NN glass))))))) (. .)))