When buying pure essential oils always check out the feedback of the seller from previous buyers as this is always a good starting point. Pure essential oils are not diluted. You should be able to trace the oil back to batch numbers if needed, sold in dark glass bottles and if possible with dropper caps as this will prevent using too much oil and accidents occuring. When buying essential oils, carrier oils and absolutes always buy the best you can as this is an area where quality does matter. Ask as many questions as you need to and most people will be happy to provide you with as much information as they can. You will find that most aromatherapists will always offer advice when asked. Most of all enjoy your essential oils they have wonderful healing and calming properties and are there to be enjoyed... Ruth... bluerockoils2002