All fragrance oils are sold in a 1/2 oz. amber bottle;
The supplier I purchase these oils from explains that these oils do have a carrier oil mixed in with them. I have been using and purchasing these oils for a very long time from the same supplier and feel they offer the best product.
When I use these oils, I still mix them with a sweet almond carrier oil if I plan on wearing the oil because some scents are very strong. I also use these oils in Oil Burners and tea lite candles for its aromatherpy effects.
Oakmoss is used a lot in Earth Magick. It is an oil that is used for grounding, and banishing. This is a great oil to use when honoring the crone aspect of your life, especially Cerridwen.