Cloque is French for “blistered”, which seems obvious since the appearance of the fabric looks like little puckered blisters of fabric. Cloque is a plain woven fabric and the blistering is created by embossing the fabric. Embossing occurs when the fabric is passed between two hot engraved rollers, which creates the design. Now, in polyesters and velvet, the design is permanent by way of melting the fibers (polyester), or pressing flat/trimming the pile (velvet).
For silk, though, in order to make the blistering a permanent feature of the fabric, a resin finish is applied. According to Fairchild, resin finish are “chemically reactive materials that may polymerize and/or form covalent cross-links in or on a substrate such as a textile.” That’s a lot of science speak for the resin protects the blistered effect on silk fabric.
Without that resin, there’s a good possibility (although without testing I can’t say for certain), that the blistering would be pressed out during ironing. On that note, when caring for this fabric, shoot for a cool iron and minimal steam. Heat and pressure put the effect in place…Pretty sure like an angry parent, it can take the effect out as well.