These three maple specialty appearances have alway's been around just not appreciated until recently. Once they became desireable these woods were then scrutinized for perfection. Quilted Maple has never been a big money maker for the large producers, primarily because it is very difficult to estimate what sort of yield any one log might actually have. As a result, the highly scrutinized appearance and lack of availability has driven the cost to an extreme. Cluster, muscle/angel wing is an appearance that lands some where between burl and quilt. It has a tendancy to be a little more brown in tone plus the waste factor is more like burl. We have built some awesome doors and panels with this wood though. Spalted/rustic maple has alway's been around but for many years was used more for backer and not so much for decorative panel because it just wasn't a particuarly popular look, therefore, it just wasn't profitable for the producers to pursue as decorative. Accept for the odd log, it still isn't all that popular so a big portion of it still ends up as backer just like it traditionaly has. We do keep a small amount of quilt around and typically acquire it in larger quantity's as needed. We do have a fair amount of cluster and a really nice spalted flitch.