The Specific Gravity and Viscosity of a substance directly relates to the density of that substance compared to a reference (usually water).
In this image, the liquid on the right has a higher specific gravity due to it having a more “dense,” “sticky,” or “viscous” structure when dropped or poured. The liquid on the left therefore has a low specific gravity, due to its thin structure and easily pourable nature.
Example of an Oil with a Low Specific Gravity:
Green Mandarin: 0.85
Example of an Essential Oil with a High Specific Gravity:
Sweet Birch 1.14
The reference that we use when testing essential oils' and carrier oils' specific gravity is water, which has a specific gravity of 1. This means that any oil with a specific gravity below 1 has a structure similar to the liquid on the left in the image, and conversely, an oil with a specific gravity above 1 has a structure similar to the liquid on the right in the image.
The Viscosity and Specific Gravity measurements are two of the five "fingerprint" tests that we use to identify any possible inconsistencies among the oils. These measurements can be found in the "Technical Data" section of each essential oil's Certificate of Analysis. If the viscosity and specific gravity of an essential oil or carrier oil tested at Ananda varies significantly from previous batches, this could be an indicator that that oil may be contaminated or adulterated.