Duck Eggs

Aside from being larger than chicken eggs, duck eggs have different material qualities and react differently to the vinegar than the chicken eggs.

Whilst in vinegar the chicken egg shell dissolves layer by layer relatively ‘as one’, the duck shell, like the layers of a sedimentary rock or a particularly thick toe nail, comes away in flakes.

However, the duck egg shell responds well in the heated vinegar.  A far better solution of a clean removal of the hard shell.

Duck egg shells have an altogether more rocky or marble-like quality than their chicken counterparts which I think of more like a ceramic material.

Secondly, duck egg membrane is thick, rubbery and less malleable than membrane from a chicken egg.  Thus, I have found it to be an unsuitable material for taking impressions.

First Impressions

Taking strips of the deflated egg membranes, I pressed them to the surface of a vaselined vintage aluminium jelly mould.  To my suprise, the membrane bonded together really well and has continued to hold its form.

It is worth noting that the addition of vaseline as a release agent causes the membrane to be less brittle and have a slightly shiny, translucent finish rather than the white, matte, opaque surface of membranes that have simply air dried.

Impression of Toby jug face

This trial was attempted without any release agent, so it is unsurprising that the membrane, which shrinks when it dries was difficult to remove.

Deflated Chicken Egg Clumps

I made the mistake of leaving a collection of blown eggs in vinegar solution for too long.  The perfectly blown egg membranes had deflated, with the air escaping from the high pressure of the interior out through the pores of the egg membrane and bubbling to the surface.

Cross Species Egg Clusters and Casings

Common Whelk cluster. A Common Beach Combing find.
Giant Atlantic Whelk excreting? its egg casing.
Common Whelk Egg Cluster
Dried out Common Whelk Egg Cluster
‘Sand Collar’ the huge egg cluster of a moon snail
Not a seal slug, but another example of a moon snail egg cluster, only this one has yet to be covered in sand
Extraordinary examples of the Giant Atlantic Whelks’ vertebrae-like egg casing. Twisted like the skeleton of a monstrous sea serpent.

30 min mark

After 30 minutes, I made the mistake of taking the eggs after they had been submerged in simmering vinegar and washing them under cold water.  This change in temperature shocked the eggs and caused some of the shells to crack, damaging the membrane underneath.

Nevertheless, I love the material qualities of the egg shells at this point.  Their terracotta colour is paired back, emerging as an uber-matte, pebble like pastel.

De-shelling equipment

Using a steam cooker, I decided to try heating whole eggs in vinegar for 1hr 30mins and leaving them submerged over night.  As I am looking to purely extract the membranes to make impressions, it would be unnecessary to blow all the eggs as I’ve found I can peel the membrane off the hard boiled eggs.

Experiment Report

12% Acetic Acid White Vinegar as opposed to 5% concentration used previously.  Most commercial vinegars for consumption and cleaning are 5% Acetic Acid or lower.

1 PBB Duck Egg
1 PBB Chicken Egg, NOT BLOWN
2 Previously blown Chicken Eggs
1 Fresh Chicken Egg

(PBB = Past Best Before)

Within 10 minutes the higher PH vinegar has eaten away at the coloured outer shell layer.

Will update with how the vinegar performs under low heat and to what extent the addition of heat accelerates the ‘de-shelling’ process.