A necklace worth £10 was stolen from the Mind charity shop in Maldon High Street.
Two suspects are believed to have taken it at 2.15pm last Monday.
The first was a white man who was about 6ft 2ins tall, aged about 30, and wore a white T-shirt and black shorts.
The second was a white woman, about 5ft 3ins tall, also aged about 30, with dark collar length hair and wearing an orange and pink jacket.
Call Maldon police on 101 with any information.