Society6 The Mountains Are Calling, And I Must Go. John Muir. Vintage. Mug 11 oz * * * * * Buy with confidence: Only products sold by Society6 feature genuine Society6 quality and ensure that the artist gets paid for their work * * * * * Our premium ceramic coffee mugs feature wrap-around art and large handles for easy gripping. Dishwasher and microwave safe, these cool coffee mugs will be your new favorite way to consume hot or cold beverages. Available in 11 and 15 ounce sizes. An independent artist profits from every purchase with Society6.