Step 16 is in reference to the steps on this page, https://www.kintugi.com/?page_id=80
This video shows finish work on silver, the final set in kintsugi.
The supplies are available here, https://www.etsy.com/listing/150669515/hon-urushi-finishing-lacquer-for?
For more on kintsugi see https://www.kintugi.com/