What you can see is metal capping. It's main purpose AFAIK is to keep the cable tight to the wall for plastering. So long as there's no danger of the wire being damaged by any sharp edges on the capping you'll be fine plastering over it.
@wvm started
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What you can see is metal capping. It's main purpose AFAIK is to keep the cable tight to the wall for plastering. So long as there's no danger of the wire being damaged by any sharp edges on the capping you'll be fine plastering over it.