Given it's got white splodges, I reckon this is Heron. It just doesn't look like Ditchfield's work at all.
I picked up a white splodgy Heron labelled mushroom last wek, it's base has sort of polished edges, but a slightly patchy rough-ish sort of bit in the middle.- a few scores on the flat surface.
I don't have a Ditchfield mushroom to compare. Just an apple and 3 (unique numbered) vases.
The apple has a polished rim to the base and a roughly ground out, completely round pontil scar depression.
The iridesence on Diitchfield stuff iIconsider to be more "oily" in hue that that of Heron, which I tend to describe as being "rainbowy bright".
But that might just be because of the darker colours Ditchfield uses underneath.