I had thought there may be a variant spelling and possibly be Masson or Maeson or Maison.
Also van Soldt family were part of Austin Friars, Dutch Reformed Church of London England before coming to Virginia colony in 1650's. I think there was Mason families in there too, or maybe part of the Wallon Church in London. You can find books in GOOGLE BOOKS author is Moens or at www.Parishchest.com . They may have been Dutch, Belgian, Flemmish, or Hugenouts displaced there by wars with the catholics.
Northampton County Orders & Wills 1678 - 1683 BOOK 11. Transcribed by Frank V. Walczyk. Price $43.50 - NH011 - Abraham Vansoldt, Abraham Vansolt p. 3.
It is ordered by the court upon the petition of Joseph Mason who married Rose the daughter of Abraham Vansoldt that the said Vansoldt forthwith deliver him such estate as belong unto her paying charges of court.