About Trethewey Artisan Stone Trethewey Artisan Stone, granite, marble, quartz stone, engineered stone, benchtops, bench tops, vanities, fire surrounds, hearths, kitchen, kitchens Trethewey Artisan Stone is a leading supplier of granite, marble and quartz stone surfaces throughout the South Island. Specialising in Kitchen Bench Tops, Bathroom Vanities and Fire Surrounds, from standardised plans to customised designer projects.