With Christmas around the corner, there will be countless people unwrapping the usual: socks, gift cards and chocolates. However, some gifts have the potential to grow in value in 2025 and offer attractive returns for future sellers. Vintage furniture, gold and silver jewellery, and celebrity memorabilia are among the so-called 'passion assets' that could add to your collection and boost your portfolio at the same time. The market for these collectibles is already worth $372 billion and is expected to grow to $522 billion by 2028.