As for its eco credentials, Akt has a stylish recyclable aluminium tube and cap, and comes in cardboard boxes. The deodorant is applied using your fingers, although you can also buy a small bamboo spatula (50p) to get it out of the jar. Aluminium spray cans often have some plastic parts, such as nozzles and lids, that are harder to recycle, while aerosol sprays have their own environmental implications.

Dr Olioso says: 'It contains good active ingredients, so should be effective, but be aware that arrowroot - the most abundant ingredient - might leave white marks.'

Ingredients:

This product is a crystal made from potassium alum - a natural mineral salt - and sits on the surface of the skin in a microscopic layer, where it kills bacteria. Ammonium alum is another one you'll commonly find in this type of product. You can rub it up and down or use a circular motion. Continue adding water to the stone and applying it until you feel you’ve covered your entire underarm. One user told us the deodorant had done a 'decent' job but that it sometimes needed to be reapplied during the day. Making the switch at a time when you don't have lots of high-stress work, activities or social events will take the pressure off. Stone crystal deodorant can last several months. However, it has the potential to develop an odor after some time. It will be less likely to develop an odor if your underarms are free of hair.

The brand claims Akt, developed by two West End dancers, has been tested on more than 1,000 professional dancers and athletes. It's claimed to be plastic, aluminium and cruelty-free and to absorb both wetness and odours (although it stops short of classing itself as an antiperspirant). Some people find that they go through a 'detox' period of a few weeks as their pores gradually get rid of antiperspirant build-up, and this can temporarily lead to additional sweating and odour.Bearing in mind that deodorant is simply a product that reduces body odour, then yes: Salt of the Earth is absolutely effective. However, many of us tend to use the term 'deodorant' as a catch-all for products that are also antiperspirants – aka formulas that plug your pores and stop you from sweating. Our Mineral Deodorant Stone revolutionized the deodorant category when it first launched in 1984... It's been a fan favorite ever since! #CrystalDeodorant #TheOriginalCRYSTALDeodorant