Gilding with Gum Ammoniac.

We have been asked quite a few times 'How do I use Gum Ammoniac'? So we have produced this small guide on the general process, but please understand we would not profess to be Gilders, in fact this is the 'newbie's' guide to using Gum Ammoniac. Being fairly new to using this product, it did make for interesting experimentation and any mistakes we made, will hopefully help you not to make them!

How Gum Ammoniac is made.

Gum Ammoniac is a Traditional glue for gilding using gold leaf, it is made from the dried sap (gum) that has oozed from damage to the tree Dorema Ammoniacum.  The gum is dissolved in water, all the floating debris is then removed (bark, grass etc), the liquid is then filtered through very fine mesh to remove more of the smaller debris and finally through muslin - often more than once!

The solution is a pale buff colour and will settle out, so a gentle stir before use is recommended - try not to make bubbles! The sediment at the bottom of the jar will be 'a stringy, sticky, mass' and if it doesn't form a smooth liquid, stand the bottle/jar in hot water whilst stirring.
Tip: For some the smell can appear to have a dry, acrid, vinegar aroma, whereas for others it's just an earthy, herby, quite pleasant smell. In normal use, the smell is hardly noticeable or offensive.

Applying Gum Ammoniac.

You can apply the Gum Ammoniac solution with many things but a dip pen or brush is perhaps best, but wash them immediately after use in hand hot soapy water or use Zest-it Brush Cleaner/Pencil Blend to remove the residue before washing.

Gum Ammoniac can be applied to paper, canvas, wood, metal, leather and other surfaces. The absorbency of the surface will affect the drying time and thickness of the gum.
After the gum has dried you reactivate it with warm breath, 'hurr on it' like you would to clean a pair of glasses or use a drinking straw. Be aware, the drinking straw method can cause saliva to add too much moisture to the gum.
Image right shows the wet Gum Ammoniac applied to 90 lb pastel paper using a brush.
Tip: If you want, 'nice, rounded, slightly raised, berries' try using the handle end of a paint brush.

Applying Gold Leaf to the design.

Transfer Gold Leaf usually comes in small booklets, with the thin and flimsy gold leaves lightly attached to one side of a waxy paper, this stops the gold sticking to any and everything. The spare, waxy paper area, around the edge of the gold leaf, allows you to transport and position the leaf without problem. Tip: Don't let this booklet get warm (near a radiator for instance) - your gold leaves may not be as transferable anymore!

Once the gum ammoniac is dry (image right shows it almost dry) and you've breathed warm breath on it, you can apply the gold leaf.
Cut a small piece of leaf, that will cover the design with some to spare and gently apply to the GA surface, as fast as you can after 'hurring' on it. Press the gold to the surface, gently rub (burnish) with your finger tip. Lift the transfer paper away.
You can use a piece of glassine paper or thin paper with a very shiny surface, to burnish it more, using your finger tip, or an agate burnisher, if you have one, or a smooth crystal.
 

This is quite a leap of faith if you've not done it before, the transfer paper obscures your view, just persevere and when you feel it's right, lift off the transfer paper. You may find that not all of the surface is covered, pick up some spare transfer leaf and repeat the process, until the design is covered. Remove any excess with a soft haired brush.

In the image on the right, the gold leaf has been applied to the 'berries', although it doesn't show the brightness of the gold. I tried applying the gold leaf to the stems, but found I hadn't put enough Gum Ammoniac on the surface to make a good base for the gold.
You can see in the 'almost dry' image above, there was actually very little glue on the surface of the stems. So, don't be mean when you apply the GA, make sure the surface is well covered - very wet, the thickness of the glue will reduce in size as the water evaporates off.
It was easy to work with once the Gum Ammoniac properties were understood, the finish was good and the gold shiny.
Gum Ammoniac stays workable for at least 900 years! So you can always go back and reactivate it to make repairs!

A few Hints and Tips.

If you are using porous paper apply one coat of GA, allow this to dry, it will act like a 'size' for the paper. Then apply another coat of GA, this will ensure you have enough glue for the gold to stick to.

It's easier to make true 'round' areas when the GA is applied from the handle end of the brush, touch the surface with the handle.

Gum Ammoniac gilding works best on a humid, airless day. Image right shows that sometimes things don't go as planned!

Don't use lots of pressure when you burnish, it will cause the GA to soften.

Make sure the surface of the GA has no saliva on it or your gold will slide off.

To build a 'cushion' of GA, if you are after a raised effect, apply a few layers of GA allowing each application to dry in-between - for more instant embossing use Improved Gold Body.

Try this unusual medium to give your work some 'pizzazz', it works best for small areas, vines, leaves, tendrils, etc. Apply the GA to the centre of an area and work it into any tight corners by teasing from the central reservoir of liquid. Remember you can always repair, remodel and rework any mistakes.

Gum Ammoniac and other decorative finishes.

If you don't want to use Gold Leaf, try the 'bronzing' powders.
These stick well to the surface and you have a variety of colours to choose from. Dust them gently onto the activated GA with a fairly soft brush of suitable size, cover with glassine and rub gently, dust off the excess with another soft brush. The 'bronzing' powders are incline to tarnish, so they will need a coat of varnish.

The Mica Flakes also work well, although the finish may be more subtle but more than one coat can be applied. These Pearlescent powders are inert and therefore don't need a coat of varnish and will retain their brightness.
The image on the right shows one application of the blue mica flakes on a black surface, but not the lovely shine!

You can have fun and experiment with this medium to find out what decorative finishes can be achieved - a little goes a long way.
For a less traditional glue, to give a decorative finish using Gold Leaf or powders, try the Ormoline Gilding Medium this works in a very similar way to GA and is also easy to use.

Gum Ammoniac    Ormoline Gilding Medium     Mica Flakes Improved Gold Body 

Copyright Jacqui Blackman 2005