Final answer:
Mardi Gras Indian costumes are hand-sewn, unique pieces that take about a year to create, reflecting a deep commitment to cultural tradition and artistry, and are not typically available for purchase.
Step-by-step explanation:
Mardi Gras Indian costumes are intricate works that reflect a rich cultural tradition. These costumes are not typically available for purchase, especially not as commercial Halloween costumes or even readily available during the Mardi Gras season. Instead, the costumes are often sewn by hand, a process that can take approximately one year. Each costume is unique and may feature complex beadwork, feathers, and other embellishments, much like the traditional and ceremonial Sioux dresses which were also handcrafted with meaningful symbols and intricate beadwork. This dedication to the craft is a reflection of the wearer's commitment to celebrating their culture and displaying their artistry during the festive Mardi Gras period.