Pin by Kimberley Laws on Bert The muppet show, Sesame street, Cover art Bert (Muppets) Sesame Street Sesame street, Muppets funny, Muppets Bert Through the Years Muppet Wiki. Metal: Sterling Silver Backing: Lever Back Length: 1 3 4" Width: 1 2" Amber is hardened tree resin from prehistoric forests 40 50 million years ago. Though its transparency and color varies, the most common colors are orange, yellow and brown. Amber can also range into milky whites and deep reds. Your piece was designed and set in sterling silver by Polish craftsmen. The amber carried at Green River Silver Co. comes from the Baltic region and is imported directly from Gdansk, Poland.