The NBS Classification and Competition Guidelines states that studio buttons full under Section 23 - Specific Types, and Section 23-11 "Studio Buttons Assorted, are in placed in Division III."
"Designed and fabricated primarily for sale to button collectors. They are not mass produced, but are hand-made in limited quantity and express the maker's artistic creativity. They may be the work of a single artist or a collaboration. Jewelry, craft pieces, and natural objects (such as shell, walnut shell slices or stone) to which a shank has been attached do not qualify.) Label buttons as to make and date if possible."
The following Studio Buttons are made by members of the Ottawa Valley Button Club
June Chambers has created fabric buttons button!