What possible intersections can we identify in a hybrid zone between Jewellery and Product Design? We present a reflection and introspection on a set of experimental projects in the jewellery field that began in 2016 and was initially framed within the scope of a post-doctorate in Design. If the Product Design field must respond to a socio-economic and cultural context, specifically to the pressing needs and problems of the world, jewellery can also consider the same problematics and involve similar creative processes. The so-called author's jewellery is free from certain constraints arising from mass production, taking advantage of the historical relationship it establishes with the Fine Arts. In this approach to the affinities between two fields that have their disciplinary autonomy, we are interested in asking how Jewellery can benefit from Product Design both at a methodological level regarding the adoption of principles of sustainability that consider society and culture and from a more rational design perspective based on modularity, among other compositional strategies. Considering that a product is not exhausted in its physical dimension, but also in its ancestral dimension, the dialogue can be awakened in the opposite direction, because a jewel will always be an emotional product.