Leather Envelope Clutch
You can have this acrylic pattern from here:
http://www.leathercraftpattern.com/leather-envelope-clutch-acrylic-template-pattern-A-127
The finished size is about: 11" x 7" x 0.8" (28cm x 18cm x 2cm).
Advice:
Hardware: 17cm No.3 zipper x1, No.3 slider x1, 15mm magnetic button x4.
Leather: We advice 1.0mm (2.5oz) leather, size 45cm x 90cm.
Tools: If you are a new leather player, try to considerate to have tool kit here: http://www.leathercraftpattern.com/leather-tools-leathercraft-tools/leather-tool-kit/leathercraft-tools-leather-craft-patterns-leather-art-leather-carving-tool