Is there any concept about low or Heavy weight oil in essential oil?

[runasyrst]

Is there any concept about low or Heavy weight oil in essential oil?
Is there any spices that classified as low or Heavy weight oil when steam distillation?
Are we need salt with Lavender , Lemon or other plants during making essential oil via steam distillation?
 

[Strange]

Maybe not relevant but interesting: http://www.bbc.co.uk/news/health-43429933

Quote

More evidence essential oils 'make male breasts develop'

 

Edited March 18, 2018 by Strange

[John Cuthber]

Some essential oils are denser than water (for example clove oil) , others are lighter. (for example tea tree oil) 

 That will make a difference if you are steam distilling them.