Jerte is a durable and reliable glass made from fully tempered glass from rim to foot. It has been thermal shock tested to 135c and can withstand temperature changes from hot to cold. It offers you the assurance that comes with the internationally recognized quality of glass makers Vicrila who were founded in 1890 and are one of the oldest surviving firms in the Basque Country. In addition the glass has the benefit of being fully tempered making it up to 5 times more resilient than standard glass and shattering into safer, small pieces should it break.