I got loads of recipes. Bath bombs I make by using 3 parts baking soda to 1 part citric acid. Mix well together. Then add essential oils & mix in. Then add enuf of a base fatty oil, like almond or lite olive, to make it just stick together. Bung into shapes & leave to set.
The bath salts, I usually just make from epsom salts & essential oils. Altho' you can put sea salt in as well. I tend to only use the finely ground sea salt tho' coz the coarse doesn't dissolve properly & you get a scratchy butt which is not very relaxing ! I avoid putting things like whole herbs & flower petals in my bath bombs coz they look pretty in the bath bomb, but all they do in the bath is float on top & stick to your skin & are really difficult to get off if some form of base fatty oil is involved too. If you want a herbal bath, I find it's best to just add a strong tea or tie a muslin bag full of herbs around the hot tap & use it like a tea bag.
I usually calculate amounts based on a total of 6 drops of essential oils per bath. Taking into account things too like photosenstivity ( ie no bergamot oil etc. ) & things like no known sensitisers such as cinnamon oil too & relative qtys of oils etc. Mind you, I've known people have sensitisation reactions to even something as innocuous as lavender. With possible sensitisation reactions, you need to keep in mind, is the person this is for atopic in any way ( excema, asthma, hayfever etc ) & less is more & vary your blends. It's often constant daily use that causes reactions. You know like continual butt wiping during nappy changes with the same oil, daily massaging of other people with blends containing the same oils & so on. The other thing to watch out for is pregnancy & by this, I don't mean the usual list of not to oils, but rather your skin changes during pregnancy & can get far more sensitive. I remember one particularly unpleasant experience where I decided to go for the classic pregnancy oils in my bath - lavender & mandarin. I only put one drop of mandarin in there & I ended up with some very painful itchy red welts where it had burnt my skin. Dilution in a base oil like in a bath bomb probably would have stopped that, but even so - yuck!!! Anyways, I digress.....
here is the sea witch recipe ( from Scott cunningham ) which I love. It's a bit naughty coz it uses a drop or so of fake musk oil. You can leave it out but the scent is not quite the same. I figure on the general scale of things, unless you're totally organic with absolutely everything, it's not that bad.
Definitely avoid if you get any skin issues tho'
You need for 4 bath bombs
300g ( approx 12oz ) baking soda
100g ( approx 4oz ) citric acid
8 drops lavender essential oil
4 drops rosemary essential oil
4 drops ylang ylang essential oil
4 drops musk fragrance oil
2 drops jasmine absolute
2 drops rose absolute or steam distilled essential oil
Mix all ingredients well together until oils are evenly distributed in powder. Mix in enuf lite olive oil or almond oil or other suitable base fatty oil to make mixture just stick together. Put in moulds & leave to set.
If you have skin issues & don't wanna risk bath bombs with eos in. Note btw that the jury is still out on the issue of skin absorption. It's the political hot potato of aromatherapy. What you can do is make the bath bombs without any essential oils at all so you get the skin softening effects & simply use a diffuser with the desired blend in the bathroom so you get the aroma while you're in the bath.
enjoy
