凱倫．布朗寧（Karen Browning）用窯鑄的橢圓黑色玻璃鏡進行實驗。作品《雙視界》（Double Trouble 2019）以脫蠟鑄造加上冷工拋光與噴砂、24K鍍金。她對於鏡子的暗喻意象和對熟練的製作工法，在此作品中清晰可見。內在與外在，物理、文化與心理的層面，過去、現在、未來的時間軸，全部納進作品，自我表述對鏡子的思考，並展現其深度思維：
Andrew Brewerton said……
Karen Browning (1969) experiments with black cast glass spheres and their capacity for surface reflection. Double Trouble (2019), is cast in black glass using the lost wax process with subsequent cold-working – polishing and sandblasting – then gilded with 24-carat gold. The artist’s pre-occupation with the mirror motif draws consciously on complex historical reference, while focusing on the immediate presence of the glass artefact and its making. In the play of inside and outside, physical, cultural and mental dimensions, past, present and future, all surface in the visible moment of the glass studio.
As Browning writes, of her interest in mirrors and their various depths:
In these pieces I explore the historical and mystical side of black mirrors, traditionally used for scrying (looking into the future) whilst also combining this with historical use of black mirrors by landscape painters such as [the French baroque painter] Claude Lorrain [c.1600-1682]. Mirrors create another space, altering or confirming a sense of self or place, and through deception, illusion, and reflection provide a luminous space for contemplation.
 Karen Browning, ‘Experimenting with black cast glass sphere and reflections’, quoted in Peter Johnson and Karen Browning, 50 years on: the heterotopian mirror of enchantment, self-reflection and disruption, at
http://www.heterotopiastudies.com/wp-content/uploads/2017/03/Mirrors-50-years-on.pdf . “Using mirrors to foretell the future – ‘scrying’- was practised by the ancient Egyptians, Sumerians, Hebrews and the ancient Chinese. The Italian physician Girolamo Cardano (1501-1576) devoted 14 chapters of his treatise to the ‘miracles of catoptrics’, the ‘natural magic’ of optical manipulations, describing different types of mirrors that make it possible to invert, multiply, make distant, draw near or fragment an object in space.”