DesertGold/Moorcroft: https://www.desertgold.us/moorcroft/Moorcroft.html
Moorcroft Pottery HIBISCUS (Walter Moorcroft) Cobalt Blue Triangle Ashtray Approximate Dimensions: 5.25" (13.335 cm) diameter .625 " (1.588 cm) high Circa: 1970s Stoke-On-Trent, England