The tangram is a dissection puzzle dating back to 18th century China, and consists of seven geometrical shapes ('tans') which can be arranged into a square, and into a multitude of interesting shapes - including a beautiful heart.

This handmade card is ideal for Valentine’s Day, but has been left blank inside for your own message so it can be used for anniversaries, birthdays and other special occasions too. It's available in two versions: a rainbow on a rectangular card, or a square card in shades of pink.

The seven tans have a 3D effect, but the designs are slim enough to be mailed using a standard letter size postage stamp.

The pink design has a diamanté heart on a mulberry paper background, and is made from white hammered 300gsm card and is approximately 12.5cm square; it is supplied with a smooth white 100gsm envelope, both of which are manufactured in the UK.

The rainbow design is mounted on a white pearlescent background, and is made from brown kraft card measuring approximately 12.5cm x 17.5cm; both the card, and its matching 120gsm envelope, are manufactured in the UK using recycled post consumer waste.