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Mike Bullivant's Diary

Day 12: Hand cream

Mike with lanolinWell, the lanolin didn't freeze out overnight, even though we had a very heavy frost. So we have to try an alternative way of purifying our dark-brown oil containing the lanolin. Then I have a brainwave. I'll try a little trick that we chemists often use to purify organic chemicals – a process called solvent extraction. There's some olive oil in our storeroom in the sawmill. As we all know, olive oil and water don't mix. If I take some of the impure lanolin oil, shake it up in a bottle with some clean brine (water containing table salt) together with a smaller amount of the olive oil, the lanolin, being a grease (a solid fat), will prefer to dissolve in the upper, olive oil layer rather than the lower, water layer.

I can't believe what happens when I shake the bottle. All of the coloration in the impure lanolin oil is taken up by the water. More interestingly, an off-white ‘solid' has formed as a separate, third layer between the olive oil and water layers. Given the amount, this can only be pure (or at least, much purer) lanolin. The purification process couldn't have been simpler. All that remains is to decant off the olive oil, and scoop off the lanolin. If our lanolin contains a little olive oil and water it won't matter – it will be pure enough for our purposes.

Group testing hand creamTo make the hand cream, we merely add the lanolin to some molten beeswax that we've been given. To perfume it, we stir in some tea-tree oil that I've extracted (using steam distillation) from some leaves Ellen collected for us. The cooled mixture is fragranced lanolin hand cream. Not bad, even if I do say so myself.

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Photo: Mike Bullivant
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