( ( ( ( ( As ( ( the mineral ) cools ) ) ( , ( ( the ( crystal structure ) ) ( begins ( to form ) ) ) ) ) and ) ( ( diffusion ( of isotopes ) ) ( is ( less easy ) ) ) ) . )
(ROOT (S (S (SBAR (IN As) (S (NP (DT the) (NN mineral)) (VP (VBZ cools)))) (, ,) (NP (DT the) (NN crystal) (NN structure)) (VP (VBZ begins) (S (VP (TO to) (VP (VB form)))))) (CC and) (S (NP (NP (NN diffusion)) (PP (IN of) (NP (NNS isotopes)))) (VP (VBZ is) (ADJP (RBR less) (JJ easy)))) (. .)))
As the mineral cools, the crystal structure begins to form and diffusion of isotopes is less easy.
(ROOT (S (NP (JJ Mineral) (NNS crystals)) (VP (VBP are) (VP (VBN formed) (SBAR (WHADVP (WRB when)) (S (NP (JJ hot) (NN lava)) (VP (VBZ cools)))))) (. .)))