Petrol Hexagon, plakater i gruppen Plakater og posters / Grafisk hos Desenio AB (8529)
Such a beautiful pattern by, apparently, Sophie Digard. Can't find instructions anywhere but on inspection it looks like randomly sized rings of double (US: single) crochet into which chain loops (5 to 7 chains I think) are stitched and joined as you go. May try this.
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