“…Scapolite is an obvious candidate for detailed investigation by this technique; however, our early attempts to outgas this mineral by conventional stepped heating experiments demonstrated significant fractionation of the noble gases (below). The present investigation was initiated after the publication of 40 Ar/ 39 Ar ages obtained by in vacuo crushing garnets Wijbrans, 2006, 2008), suggested significant quantities of lattice-hosted noble gas could be released during prolonged in vacuo crushing experiments (Kendrick, 2007;Kendrick and Phillips, 2009). In contrast, only minor release of He and Ar, from olivine, clinopyroxene and mica matrices, has been demonstrated by in vacuo crushing studies previously (e.g.…”