What Staining/antiquing Process Was Used To Make This?

[SouthernCross]

http://www.etsy.com/listing/157719140/handmade-wallet-cowhide-carving-genuine?ref=sr_gallery_34&ga_search_type=all&ga_includes%5B0%5D=tags&ga_search_query=leather+carving&ga_page=2&ga_view_type=gallery

[mlapaglia]

You can achieve that look by coating the tooled area with a resist like resolene or super sheen. Then dye the leather except for the tooled area. once the main dye is done using some antique dye on the tooled leather and wipe it off right away. it will stay on the tooled area and come off of the higher (untooled) area of the leather.

Thats not a very good explanation but its a resist method of antique dye application.