I don't believe this is intended, but selling back the refine recipe to the shop gives you the L2 version of ore instead of the percentage buyback of the credits used to buy the recipe. This allows you to easily turn credits into a large number of L2 ores (depending on recipe/recipe buyback values in the server.cfg).
This behavior also happens with purchasing manufacturing material recipes from the shop (i.e. processors, expanders, paint, protein, etc). For example, rock can be turned in for a brown paint recipe, and that recipe can subsequently be sold back to yield brown paint (instead of rock). This circumvents the need for actually using the recipe as the shop essentially is acting a go between recipe.
This behavior also happens with purchasing manufacturing material recipes from the shop (i.e. processors, expanders, paint, protein, etc). For example, rock can be turned in for a brown paint recipe, and that recipe can subsequently be sold back to yield brown paint (instead of rock). This circumvents the need for actually using the recipe as the shop essentially is acting a go between recipe.