The term 'AMBER Source' is a combination of two crossword solutions: RESIN (5 letters) and AMBER (5 letters). AMBER is a fossilized tree RESIN that has been used for centuries as a gemstone, jewelry, and decorative material. RESIN is a natural or synthetic substance that is used in many products, including paints, varnishes, adhesives, and plastics. The combination of these two materials creates a unique source of AMBER, which can be used for a variety of purposes.