So which candles should we be using? There is no black and white of which candles are the best, but some are definitely better than others. There are bazillions of great candles on ekko.world if you want examples of what to look for. In reality, there are pretty much three things in a candle. Wax, a wick and, where relevant, fragrance.
Beeswax and soy candles are generally a better alternative to petroleum based candles.Only buy 100% beeswax candles or 100% soy candles. There are a lot of fake candles around that advertise that they are beeswax or soy candles when they actually only contain small amounts of beeswax or soy.
The main thing to check for with fragrances is how they are made. What you want to find is a list of pure essential oils and what you don't want is a chemical cocktail that produces a scent. (I personally find that 'scents' are thinner smelling and a little sickening.)
Choose lead free, natural fibre wicks. According to candles.org, "most high-quality wicks are made from braided, plaited or knitted fibers to encourage a slow and consistent burn. In general, twisted wicks are of lower quality than braided or knitted wicks. They burn much faster because their loose construction allows more fuel to quickly reach the flame."
The most expedient way to check the integrity of any product is to read the label. Pretty much every natural, organic, palm oil free, fair trade, made local product will tell you exactly what is in their product. Check things like:
Paraffin wax is used in the majority of candles found in shops and can be harmful to both our health and the environment. When paraffin candles are lit they can release harmful chemicals into the air. However, the candles will not cause too much harm if used on a short term basis and used in a well-ventilated area. Paraffin candles are generally cheap to buy, however their burning rate is higher than that of beeswax candles.
Remember to trim your wick before each use. This will increase the life of the candle as well as controlling the height of the flame. It is generally recommended that the wick height be around 5mm. For a range of beeswax or soy candles see Candles.