Instruction: Generate an answer to the question by utilizing the information contained in the document.

Input:
Question: Are the covers metal? I am looking for small jars to put essential oil mixed in. Can't be plastic at all.
Document: Great little glass jars for making your own creams! I also use them to carry a small amount of coconut oil when I go to a restaurant and don't want to use dairy or the &#34;fake butter&#34;.
They were not magnetic lids as expected. I had wanted to use for spices and put them on the fridge.
So cute. I ordered these for the magnetic spice rack I am putting up in my kitchen. I am waiting on the labels to put it all together.
Love that I could use these for homemade baby food! GREAT for small amounts. Freeze well and are durable for glass.
I needed tiny jars, and these work great. The lids even vacuum seal. You can tell by the pop when you open them each time.
Really cute little jars for homemade handouts
These jars arrived as advertised.I'm going to try to turn them in to magnetic spice jars to stick to my fridge.
Arrived quickly and in perfect condition. Will be great for my pain relief skin balms and gels.Cute little jars. Tightly fitting lids.
I love it, Just perfect  storage for my honey to go ( at work ) . I highly recommend it. It seals well, it looks durable and of course beautiful .
Answer: yes they are metal.  That is exactly what I used these jars for, to mix Essential Oils (Young Living)  They are absolutely perfect, make wonderful gifts.  I need to order more.