1920s British Arts & Crafts Big Amethyst Pendant, by Edith Linnell?

A recent addition to my collection, I just had to have it! Amethyst is my birth stone (February), and I think this big, beautiful example is a winner. It came in a cute vintage bakelite box. The polished amethyst is very tactile and has a purple pink colour. Even with some cracks inside it still looks spectacular. The ornate French-style chain is typical of the British 20s A&C. It seems to have a mark but I cannot read it. Searching the web I found a rose quartz necklace with a similar mount attributed to Edith Linnell. Could this also be by her? Any thoughts?