Last month, you could barely scroll through Instagram or Facebook without stopping, mesmerised by the sight of black bath bombs disintegrating and turning bathwater into a gothic bathtime fantasy.
But, the trend has now evolved to include another of the internet's oddest crazes.
Yesterday, American healing crystal company Mystic Relics posted a photo to Instagram of their crystal-infused bath bombs.
The black bath bomb contains Amethyst, eucalyptus, grapefruit, lemon, lemongrass, and lime.
Not only does the fizzy bomb turn water jet black, it also contains a pH neutral activated charcoal derived from coconuts which, according to the Instagram sight, is 'a great detoxifier for the skin and hair as it pulls toxins out.'
Fun and beautifying.