There are many varieties of lavender that come out of the fields to make the ever popular Lavender Essential Oil. There are basically 3 different types of lavender essential oil. They all belong to the Family Lamiacea & they all have lavender as part of their name, but that is where the similarity ends.
The Latin names of the different lavenders is just about the only way to really tell them apart unless you have an expert lavender nose...lol. The Latin name of the True Lavender is Lavandula angustifolia or English Lavender as it's sometimes called or L. officinalis or L. vera. Lavandin's Latin name is Lavandula x intermedia & Spike Lavender is Lavandula latifolia.
The 'X' in Lavandin's Latin name indicates this is a hybrid & was created in the 1920's by crossing Lavandula angustifolia & Lavandula latifolia, so you could say that Lavandin contains properties of both of those.
Without going into too much about the chemical composition of these essential oils, I will try to explain a bit about their healing properties. True Lavender contains the largest amount of 'esters' which means it will have the largest degree of balancing, calming, cell regenerating & anti-inflammatory properties of the three. It also has significant amounts of 'alcohols' which bring with them anti-fungal, anti-viral, a strong bactericidal, balancing & immune-stimulant properties.
Now Spike Lavender has a significant amount of 'oxides' which bring anti-viral, decongestant & immune stimulating properties to the mix. It's 'alcohol' content isn't as much as the True Lavender, so while it shares the anti-fungal, anti-viral, strong bactericidal, balancing & immune-stimulant properties, they will not be present in the same degree.
The Lavandin -- the hybrid-- will have elements of both oils, it has the largest amount of alcohols of the three which means it's anti-fungal, anti-viral, strong bactericidal, balancing & immune-stimulant properties are likely to be the strongest of the three. It contains 'esters' like True Lavender, but not quite the same strength.
So I have always bought & used Lavender 40/42 although it is pure Lavender oil, it's make-up consists of several types lavender oils! The Lavandula angustifolia, Lavandin hybrid, Spike Lavender & yet another one not as well known called Lavandula stoechas or Topped Lavender. So it contains all the healing properties of ALL the different lavenders!!!
The thing is this....the scent & quality of lavender can & does vary from lot to lot, season to season, region to region with so many variables having an impact on the lavender essential oil. Since 40/42 is a combination of those 4 oils...the scent, impact, overall quality & PRICE remain stable! Since there are actually 38 species of lavender, it would be truly difficult to continually be able to get the same product consistently for one's customers.
So since the 40/42 has always been my favorite & my customers really seem to adore it & it does do everything & maybe more than the individual lavenders I say YES I will keep on providing this very worthy & valuable essential oil to my customers!!!
Info obtained from WestCoastAromatherapy.com & other internet sources.