be lacking of color imparting pigment or other coloring agent the use of a high grade rubber having a lighter yellow or amber color and low visible impurities and inclusions in its raw state prior to vulcanization is deemed advantageous though not essential to practice of the invention for the production thereof for example a rubber grade high grade deemed particularly advantageous for practice of the invention would be for example cv 50 cv 60 l or 3l svr and more preferably be hand selected for the lightest and most visually appealing amber color lovibond scale color of 6 or less and more preferably 4 or less it is further noted that for applications in which a naturally occurring hardness of a product after vulcanization believed to be a shore a hardness of 30 35 is satisfactory no reinforcing filler e g silica need be added to the natural rubber and is in fact preferably omitted so as to retain better clarity in the finished article however should the particular application call for reinforcement or hardening of the rubber for example where a shore a hardness greater that 30 35 is desired such as when a chew toy is intended for use with a dog known to be an aggressive chewer use of a very high surface area silica added in relatively small amounts as a strengthening reinforcing filler is deemed advantageous as being thought to have the least dramatic effect of reducing clarity of the vulcanized rubber it is also noted that while natural rubber is preferred in practice of the invention due to its superior strength and durability characteristics to presently known synthetic thermosetting rubbers such as for example styrene butadiene rubber sbr the invention is intended to include.