If you know you will not be using your lamp for extended periods, it is best to leave it empty. Pour any surplus oil carefully back into the original bottle, using the funnel supplied with your lamp. Then use your lamp until all the remaining oil is used up and it goes out on its own. Leaving a lamp filled for very extended periods may cause fragrance to accumulate in the stone making it difficult to light. If you have any problems lighting the stone after extended periods without use, follow the instructions below for "How do I clean the Stone".