SOUP98410L - Southworth Parchment Envelopes Sold as 50/BX. Parchment Envelopes have a parchment finish and are designed for use with Southworth's Specialty Parchment Paper. This design conveys Old World distinctiveness and ceremony for special documents and occasions. Perfect for use with letterheads, invitations, calligraphy and more. No. 10 envelopes are acid-free and lignin-free and are compatible with laser printers and inkjet printers. 24 lb.