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Table of fatty acid content of oils for soapmaking

  Linoleic Oleic Palmitic Stearic Iodine
      Hard bar Hard Bar value
  Conditioning Conditioning Stable lather Stable lather (see note#)
almond, sweet 20-30% 62-86% 4-9% 0.5-3% 95-109
apricot kernel 22-33% 56-70% 3-8% 0.5-3% 95-110
avocado 5-15% 45-75% 15-25% 1.5% 75-95
baobab 18-35% 20-40% 18-36% 2-8% 55-95
black cumin 50-64% 18-28% 9-16% 1.5-5% 110-125
blackcurrant 40-58% 8-16% 6-14% 1-4% 145-188
borage 34-43% 14-20% 9-11% 3-5% 130-140
camellia 5-10% 70-85% 6-11% 1.5-3% 75-95
castor ** + 5-7% 3-7% 1-2% <1.5% 82-90
cocoa butter 2-7% 29-41% 25-35% 28-38% 30-45
coconut** + 1-3% 6-10% 7-12% 1-3% 8-11
evening primrose 70-75% 5-10% 5-10% 1-2% 140-160
grapeseed 60-75% 12-25% 6-9% 3-6% 130-145
hazelnut 7-15% 68-85% 4-8% 1.5-4% 85-100
hempseed 50-65% 12-20% 4-9% 2-5% 150-170
jojoba 1-5% 5-25% <4% <1% 80-90
kiwiseed 12-22% 10-16% 2-7% 2-7% 170-205
kukui nut 35-50% 10-35% 4-10% 2-8% 130-165
macadamia 1-3% 54-60% 7-10% 2-6% 73-79
mango butter 3-7% 38-50% 11-17% 30-45% 40-55
marula 4-7% 70-78% 9-12% 5-8% 70-80
meadowfoam+   3%      
neem 8-20% 40-60% 14-19% 14-21% 65-85
olive (incl. pomace)** 6-14% 63-83% 7-17% 3-5% 79-95
palm** 3-13% 35-45% 40-50% 4-7% 48-58
peach kernel 17-30% 55-70% 4-7% 1.5-3% 95-115
pomegranate+ 7% 6% 3% 3%  
pumpkin seed 36-64% 18-47% 7-15% 3-13% 115-140
raspberry seed 55% 12% 2% 1%  
rosehip 42-49% 13-16% 2.5-5% 1-3% 180-195
safflower 50-74% 20-40% 5-8% 2.5-7% 120-135
sea buckthorn seed 40% 20% 6-10% 3%  
sea buckthorn fruit 10% 15% 30% 2%  
sesame 30-55% 40-50% 6-15% 3-6% 103-116
shea butter 4-10% 40-50% 3-8% 35-45% 45-65
soybean 48-57% 19-28% 10-14% 3-5% 125-145
sunflower 40-74% 15-40% 5-8% 2.5-7% 120-145
tamanu 30% 41% 14% 13% 84
walnut 45-60% 35% 5-8% 2-6% 120-140
wheatgerm 30-57% 12-39% 11-16% 1-6% 115-140

Some oils stand out for their special qualities in soap (** in the table), and a few stand out because of their unusual fatty acid profiles (* in the table).
 
Coconut oil ** and +
This has between 44% and 52% lauric acid and 15-25% myristic acid, both of which make a hard bar that is good for cleaning and has a great lather. But it’s low on the conditioning fatty acids, so a soap bar made only with coconut oil tends to dry the skin.

Palm oil **
This is also a very useful basic oil for soap, with its high palmitic acid content helping to give a hard bar with a stable lather, and 35-45% oleic acid giving it conditioning qualities.
 
Olive oil **
Soap made with olive oil (called castile soap) has been a luxury item for millennia. It’s great for conditioning, as it’s high in oleic acid. But it’s only medium in iodine, which means it’s only medium for hardness. An olive-oil-only soap disappears quickly because of its softness, and has almost no lather.
 
Castor oil ** and +
The only oil with ricinoleic acid, which gives a wonderful conditioning effect. It is 80-90% ricinoleic acid. This also helps give a fluffy, stable lather – but too much will give you a sticky, soft soap.

Meadowfoam oil +
This is mainly three unusual fatty acids: 13% erucic, 18% brassic, and 62% gadoleic. In some ways it is similar to jojoba oil.

Pomegranate seed oil +
Pomegranate oil is nearly 80% punicic acid, which is named after the pomegranate - punica - and is a valuable skincare oil.

# Iodine Value is a measure of the saturation of an oil or fat (how many centigrams of iodine can be dissolved in a gram of oil or fat). Saturated fats have low iodine values, and unsaturated fats have high iodine values.  In general, oils with low iodine values make harder soaps and oils with high iodine values make softer soaps.
 
Low: under 50
Medium: 51 - 100
Medium high: 101 - 125
High: over 125

Note that there are a few oils that are extremely high (blackcurrant, hempseed, kiwiseed, rosehip) or extremely low (coconut).