After spending many hours trying to find ways to darken leather without dyes, I discovered that there are several natural products that are capable of considerably darkening leather.
Ultraviolet light from the sun or artificial sources darken leather in proportion to the intensity and exposure time of the light source. Natural oils darken leather in proportion to the number of oil layers applied. While the combination of light sources and oil layering enhances the process, poor leather quality often leads to rapid darkening.
I have tested several different methods of naturally darkening leather and I have described my results below. However, it must be remembered that these methods do not provide water-proofing. You will still need to apply some type of top-coat to protect your leather from water damage.
Table of Contents
Sunlight exposure naturally darkens leather
I have heard many people talking about the effects of leaving leather in the Sun and how it could potentially darken the color of your leather. I was skeptical and decided to test this idea with a few little experiments.
I took two scrap pieces of veg tan leather and I stacked them on top of each other. I staggered the pieces in such a way that the bottom piece was exposed to the sun but also covered by the top leather.
I left the pieces out in the sun for about 3 hours.
And those results were a little astonishing. I believe that a picture is worth more than a thousand words so I have posted several pictures from my experiment so that you can draw your own conclusion of the effects of leaving a piece of leather out in the sun.
So what can we take away from this little experiment? We know that if we go out in the sun and stay there for a long period of time without UV protection our skin will burn.
Leather is the same way….it’s only skin. It will burn and change colors if it is left out in the sun without UV protection. The effect of the sun on leather is especially important in leather storage. Leather should be stored away from all light sources. I go into more detail about how to properly store leather from light and anything else that may damage it.
That was an interesting experiment, but there are a few other qualities of leather that affect how it changes colors when it is left out in the sun.
Leather quality effects how it is darkened by sunlight
As stated above it is a known fact that the Sun Life can be used to deepen the color of the leather. but one of the most determining factors is the quality of the leather that is being left out in the sun. From our research leathercrafters have indicated that lesser quality or cheaper leather tends to darken faster in the natural sunlight.
When we purchase a piece of leather we have no idea of how the natural sunlight will affect our leather. The best way for you to figure this out is to complete a test on scrap pieces of leather for every piece of leather that you purchase.
- Place a 12 inch piece of leather in the direct sunlight.
- Cover 10 inches of the leather so that only 2 inches are exposed
- After 1 hour uncover another 2 inches of leather so that 4 inches are exposed.
- After another hour uncover another 2 inches of leather so that 6 inches are exposed
- Continue uncovering 2 inches of leather every hour for 6 hours.
- Take the leather inside and let it sit for several hours
After 6 hours (test time and wait time) you will have a strip of leather that has six two-inch sections.
Each section will have been exposed to sunlight for somewhere between one to six hours. You will be able to look at the different sections to see how the sunlight has darkened the leather.
This will allow you to see how the sunlight has darkened your particular quality of leather. I would suggest that you keep the test strip as a reference so that you have an accurate “key” of how the sunlight darkens your leather.
If you are not achieving the darkening that you desire you can add some neatsfoot oil to the leather and repeat the process of sun darkening.
Thin layers of Neatsfoot Oil effectively darken leather
Another common suggestion for darkening leather without dye has been Neatsfoot Oil.
Again I decided to challenge this idea and test it for myself. But before I did a little research on the proper application of Neatsfoot Oil to leather.
Tiny amounts should be applied to the leather for the best results. Many people who dislike using neatsfoot oil on leather don’t like it because they’ve had the experience of using far too much at once.
When applied, the Neatsfoot oil will darken temporarily and then lighten up to its original color. This will happen for the first one or two applications. Excess Neatsfoot oil will cause the leather to soak up the Neatsfoot oil and darken the leather significantly. Take caution, because you won’t be able to lighten it back up.
Additionally, thick, heavy layers of Neatsfoot oil will attract dirt and dust. This can also cause a marked change in the color of your leather.
- In order to properly apply Neatsfoot Oil I followed these guidelines.
- Apply a few drops of Neatsfoot oil to a very soft cloth
- Rapidly rub it into the leather to cover as much area as you can with the small amount.
- Apply additional oil in tiny increments until the entire project is covered in the oil .
- When finished, use a clean soft cloth and briskly rub the leather to remove excess oil.
It takes some practice to use Neatsfoot oil on leather, so consider using an old piece of scrap to perfect your technique before using this powerful moisturizing agent on your project
When not to Use Neatsfoot Oil
If you have light or russet-colored tack, you may want to choose a different type of leather conditioner to use on it, since neatsfoot oil does contribute to darkening, and will change the color of your leather. If you’re not sure about how it will work on the items you want to condition, apply a tiny dab to a hidden area to see what will happen.
Neatsfoot oil followed by sunlight produces dark leather
I have read countless posts and watched videos where individuals have used a combination of neatsfoot oil and the sun to darken their leather.
A light coat of neatsfoot oil can be applied to the leather and be allowed to sit out in the sun for 24 hours. If the leather is not dark enough, the process can be repeated. This process is continued until the leather reaches the desired darkness
Ultra Violet (UV) rays from the sun have a darkening effect on Neatsfoot Oiled leather. If the leather has not been tooled it will just turn to a medium brown color.
Tooled leather will become increasingly darker in the areas of beveling and tooling. For leather that has a tooled design on it. The heavily tooled, or beveled areas of leather will become increasingly dark based on the level of the tooling in that area. Areas that have heavy background shading will turn a very dark brown, almost black if it is left in the UV light long enough.
To some who were not expecting this, it can be a problem, but for those who are aware of the effect, it can become another tool in their leatherworking.
Leather can be darkened with Neatsfoot Oil and UV lamp
If you’re in an area that does not receive a lot of sunlight, you can produce artificial UV rays by using a UV light bulb. The UV bulb can simulate the same effect in a much shorter amount of time.
You can get a small table lamp with an adjustable arm and keep it low enough down that it is only lighting the needed area.
The idea is that once you finish tooling your design, and applying your Neatsfoot Oil you will place it under the lamp to dry.
As it dries it will purposefully get darker and darker until you have a nice medium brown colored leather on the un-tooled areas, and a darker brown in the recesses, and background areas of the leather.
This will make your tooled objects “pop” out from the leather, because of the strong contrast. It also looks much cleaner than Block resisting your leather before antique dying it, because it’s a nice even coat instead of layered.
Keep in mind that this technique is only really worthwhile as an alternative to dying the leather. Dying it afterward will eliminate a lot of the effect.
You want to use this technique if you plan on leaving your item a natural-looking color.
Side Effects – There are a few side effects of neatsfoot oil that you should be aware of before using. Pure neatsfoot will eat the stitching in your leather. In order to avoid this problem, you may want to use hydrophane. This is why some leather crafters have moved to using hydrophane darkening oil.
Hydrophone darkens leather but does not condition it
This product is fantastic at darkening leather that is not coated with topcoat sealer or anything that prevents the leather from accepting oil. I love that it’s not at all greasy.
Hydrophane darkens most leather really nicely and you don’t have to be as careful about even application as you do with Neatsfoot Oil.
The only downside reported about this product is that the oil doesn’t really condition your leather. If anything it leaves it feeling a bit dry. Most users of this product have stated that they continue to treat their leather with a separate conditioner after using this product.
Unrefined coconut oil effectively darkens leahter
In the past, I have primarily used coconut oil for softening my leather, but during some of my recent experiments, I noticed that coconut oil is effective at darkening leather.
I tested several different types of coconut oils, but I found that unrefined oil produced the darkest results. I then took this a step further and placed some samples of in the sun.
The results were very similar to what happened with the neatsfoot oil.
Vaseline darkens leathers that have a top coat sealant
Vaseline is another natural option for darkening leather without the use of dyes. This method seems to be effective if the leather has been treated with some type of sealant.
But vaseline can also be used on unfinished pieces of leather. The leather has to be placed in the sun for about 30 minutes to an hour. This technique has been used to open the pores of leather so that it is ready to receive dyes and stains.
Once the leather is slightly warm you could apply a coat of Vaseline Petroleum jelly all over the leather and allow it to sit in the sun until it reaches the desired darkness.
After it has been in the sun for a few hours, the thin coat of vaseline can be wiped off with a cotton cloth. This process should effectively make the leather one shade darker. You may have to repeat the process several times to get the color that you desire.
