Portrait Miniatures: common susceptibilities

conservation, portrait miniatures

  • Portrait miniature, untitled, formerly attributed to Samuel Cooper.



    Portrait miniature
    Untitled
    Formerly attributed to Samuel Cooper
    17th century
    Watercolour on vellum

    This image shows historical damage to the lead white paint in the face – the blackened areas are due to oxidation from pollution (red circles shows the affected areas). Micrograph x10.

  • Portrait miniature, Queen Elizabeth I by Nicholas Hilliard.



    Portrait miniature of Queen Elizabeth I
    Nicholas Hilliard
    About 1586-1587
    Watercolour on vellum stuck to playing card
    Museum no. 23-1975

    The simulated jewels in Tudor miniatures were normally created using silver as a paint. The diamonds on the sitter's hair have tarnished due to oxidation (circled). Paint loss and blackened lead white can also be seen on this miniature. Micrograph x10.

  • Portrait miniature, untitled, by T. C. Thompson



    Portrait miniature
    Untitled
    T. C. Thompson
    19th century
    Watercolour on ivory
    Museum no. P. 22-1928

    Efflorescence of crystals on the paint layer. These crystals consist of magnesium phosphate, which is a natural constituent of ivory and were caused by high humidity. The miniature was already in this condition when acquired by the museum in 1928. The right hand side of this miniature has been treated using micro-crystalline wax to change the refractive index so that the crystals become less visible.

  • Portrait miniature, untitled, by Rosalba Giovanna Carriera



    Portrait miniature
    Untitled
    Rosalba Giovanna Carriera
    About 1710
    Watercolour on ivory
    Museum no. Evans.74

    This is an image taken under ultra-violet light. Areas of historical retouching fluoresce differently from the original paint layer allowing us to pinpoint old losses/damage (red arrows show these areas).

  • Portrait miniature before conservation, untitled, by Rosalba Giovanna Carriera



    Portrait miniature before conservation
    Untitled
    Rosalba Giovanna Carriera
    About 1710
    Watercolour on ivory
    Museum no. Evans.74

    This image shows an area of flaking paint and paint loss. This is a common problem with watercolour on ivory miniatures due to lack of adhesion between paint layer and support. This photograph shows the condition before treatment. Micrograph x20.

  • Portrait miniature after conservation, untitled, by Rosalba Giovanna Carriera



    Portrait miniature before conservation
    Untitled
    Rosalba Giovanna Carriera
    About 1710
    Watercolour on ivory
    Museum no. Evans.74

    This image shows the same area of the paint layer after consolidation. Micrograph x20.

  • Portrait miniature before conservation, untitled, by Peter Paul Lens



    Portrait miniature before conservation
    Untitled
    Peter Paul Lens
    Mid 18th century
    Watercolour on ivory
    Museum no. P. 8-1934

    Miniatures from mid - late eighteenth century are often painted on very thin sheets of ivory (the thickness is often less than 0.2 mm) and they are prone to warping and cracking.

  • Portrait miniature after conservation, untitled, by Peter Paul Lens



    Portrait miniature afterconservation
    Untitled
    Peter Paul Lens
    Mid 18th century
    Watercolour on ivory
    Museum no. P. 8-1934

    After treatment, which included consolidation of the cracked ivory support and minor retouching to the background.