Five (5) Hot House Glass Mark Matthews Collaboration Marbles. Three are signed by Mark Matthews and collaboration artists, the green marble is unsigned, and one is signed with the hot house logo. Dimensions: See listing picture for dimensions and artist info. Processing and shipping within the Continental US $35. All FedEx packages are sent with Direct Signature Required and insured at full replacement value for a fee of 1.5% of the purchase price, unless buyer accepts complete liability in writing. Discounts given on combined lot shipping. Marbles have a unique construction that disrupts the smoothness of the surface. This appears to be intentional from the collaboration style