I could have sworn I had it all covered with my video on how to apply gold leaf. You know that old expression “everything but the kitchen sink”? Well that definitely applied. My video, How to Apply Gold Leaf, (see it for free here) gives all the tips and tricks for creating a gold leaf surface to paint on, and then how to prepare the leafed surface for overpainting with acrylic paint. HOWEVER, it appears I was amiss to include how to prepare the leafed surface for overpainting with OIL PAINT! How silly of me. So here I go with this additional information.
Real Gold Leaf vs Imitation Gold Leaf
First I want to repeat some info from the video to mention the difference between using real gold leaf and imitation (or composite) gold leaf (made with copper and zinc). In the video I explain why I choose to use the imitation gold leaf and not the real gold leaf for my painting purposes. In summary, these two types of metal leaf look exactly the same when using a particular application method – and that is by using size (glue or adhesive) to adhere the leaf. Using real gold (involving extra expense) is worth the expense (in my opinion) when you will be showing it off uncovered, as in a frame, AND using a different application method – water gilding not size. Water gilding is extremely labor intensive, and since I cover a good portion of the leaf with paint, it doesn’t make sense for me to go to the expense of using water gilding and real gold. I know there are some good reasons some of you may have for using real gold, and that’s fine. I just wanted to share my opinion.
On left is real gold leaf; On right is imitation gold leaf
How to Apply Gold Leaf
Whether you are using real gold or imitation gold leaf, the techniques for application using size adhesive are the same. So for this process, please watch my video (link above) to get all the information on using size adhesive to adhere the leaf. However, if you plan to use OIL PAINT to overpaint the leaf, then make sure you stop the video when you get to the latter part, after the leaf is applied and burnished, and I start to talk about sealing the leaf. Since there are different considerations in sealing the leaf for oil paint vs acrylic paint substitute the following information on sealing the leaf for oil paint.
Applying Gold Leaf OVER Oil Paint
Just one word of caution before I proceed on instructions for sealing the leaf for oil painting. If you are applying gold leaf OVER oil paint, then first make sure the oil paint is fully dry. Depending on how thick you are applying it, and your climate conditions, it may take up to a month or more. Once the oil paint is dry, follow my video instructions to apply the leaf, BUT with one exception – use an oil based size adhesive, NOT the water based size adhesive. Bet way to tell the difference? The oil based size will say on its container label to clean brushes with solvents, while the water based size will instruct you to clean brushes with water.
Does Real Gold Leaf Need to be Sealed?
Real Gold Leaf does NOT tarnish. So you do NOT have to seal it to protect it from tarnishing. HOWEVER, the real gold leaf is so thin (and so is the imitation leaf) that once it is applied onto your painting, and not sealed, it can be marred if mishandled. So even though you do not need to apply ANYTHING over the real gold leaf, you may still want to seal it to add some protection from getting scratched or damaged.
Are Sealing Requirements the Same for Oil Paint as Acrylic Paint?
NO! Sealing requirements are different depending on which paint you will be using to apply over the leaf. If you are overpainting the leaf with acrylic paint, then stop reading this article and just follow my free video (link above). If you are overpainting the leaf with oil paint, then DO NOT seal the leaf before painting. The oil paint may redissolve the sealer. Instead paint with oil paint over the unsealed leaf, and when your painting is complete and fully dry, then apply a sealer over the entire painting – including both leaf areas and painted areas.
I recommend using any professional leaf sealer that is solvent based. An appropriate sealer should have on its container label instructions to clean it up with solvent, and to wear protective gear such as a mask and gloves. Check with the company that makes your leaf to see if they carry an appropriate sealer. I like to use Golden’s MSA Varnish for brush application, or the same product by Golden (but in a spray can) called Archival Varnish Spray.
Important Reminders for Acrylic Painters
Imitation leaf will tarnish TWO ways. It will tarnish when exposed to air, and also when exposed to the ammonia in all acrylic products while the acrylic is still wet. Once the acrylic dries the ammonia has dissipated and will not tarnish your leaf. SO, if you are applying acrylic paint over real gold leaf you can opt to wait to seal at the very end when your painting is complete. BUT if you are using imitation gold leaf, you MUST seal it when you have finished applying the leaf onto the surface and waited the appropriate time for the adhesive to fully dry (I like to wait a week). This means you will seal the leaf BEFORE you apply any acrylic paint or products over the leaf. I know this gets confusing, but I have to add a note here. You can seal your imitation leaf using an acrylic product IF AND ONLY IF the acrylic product you are using to seal is super fast drying, (so fast the ammonia will dissipate before it can tarnish the leaf) like the Archival Varnish Spray, Golden’s GAC200 or GAC500.
Apply oil paint directly over real or imitation leaf without any need to seal the leaf before painting.
Do not apply oil paint OVER sealers. But sealers can be applied over the oil paint.
Apply acrylic paint directly over real leaf without any need to seal before painting (but sealing the leaf may allow the acrylic paint to be applied easier.)
When applying acrylic paint over imitation leaf, the leaf MUST be sealed before painting.
It’s a good idea to seal your painting at the very end, even if you already sealed the leaf before painting. Sealing with an archival varnish enables the painting to be cleaned, and adds UV protection