Wedgwood Jasper : History
With changes in architectural styles and the rise in popularity of Neo-classical styles of interior decoration, Josiah Wedgwood began a series of experiments to create a new ceramic material that would complement the new fashions.

Thousands of meticulously recorded experiments were carried out to make a stoneware body that was capable of taking a mineral oxide stain throughout. The search for the Jasper body absorbed much of Wedgwood’s energy and time, the result being his most important contribution to ceramic history.

The below timeline, I put together only recently. This was to get a better understanding of how and when the different Jasper bodies had been produced, and what decorations were applied. I have gathered information from books, articles, corrospondence, and the Internet.

(If you have further information or corrections, please contact me.)

1730
Josiah Wedgwood born.		 1759
Ivy House Works, Burslem established.		 1762
Brick House (Bell Works) factory established.		 1769
Etruria factory established. Partnership with Thomas Bentley begins.
c.1774
Jasper body produced.

Earliest objects consisted of white on white cameos. Referred to as "Waxen Bisquit".

 1775
Solid1 Jasper items (further progressed), were introduced in the sales inventory.
Ware consisted mainly of two-toned cameos and intaglio's.		 c.1777
Jasper Dip2 utilized.		 c.1778
Trials for Jasper busts & statues occur. Very few of these larger objects survive the firings, those that do are marked "Wedgwood & Bentley".
1779
Jasper body (perfected), was introduced by name in that year's sales catalogue. 		1780
Thomas Bentley dies.		 1787
Large Jasper vases appear in that year's sales catalogue, having been successfully produced for some years. Jasper Teaware3 and dessert services also introduced.		 1790
Wedgwood's first successful copy of The Portland Vase completed.

Diced4 decoration introduced in Jasper sales inventory.
1795
Josiah Wedgwood dies.		 c.1811
With popularity waning, Jasper sales decline and production slows.		 c.1817
Production of Dip Jasper becomes dominant over the costly solid Jasper. 		c.1829
Jasper production almost ceases.
Also, it seems that without the expertise of Josiah I, the solid white Jasper body had become unstable by this time.
c.1844
Jasper production resumes.

Only Dip Jasper is available - but now the tinted liquid Jasper is layered upon a basic white stoneware body, not upon solid Jasper as before.

 1860
Solid Jasper re-introduced.

Still costly to produce, and the quality is not to the standard of the original.

Dip Jasper continues to dominate with solid Jasper reserved for prestige items.

 C 20th NOTES:
"Bas-Relief Ware" is the term used for the vast number of Jasper dipped domestic items being introduced at this time, this time the liquid Jasper is being layered over a porcelainous white stoneware body.

Almost all dip Jasper pieces made in the twentieth century come from the "Bas-Relief Ware" range, and there was often a clear glaze applied to the interiors of this domestic ware.
1908
The "MADE IN ENGLAND" mark begins general use. 		1929
The sans-serif "WEDGWOOD" marks begin general use. 		c.1941
Barlaston factory established.

Jasper production ceases due to WWII.

 c.1948 - Present
Jasper production begins again.

Items are made from solid Jasper only, but this is rougher and hasn't the fine texture of the original body.
Jasper Dip is now reserved for prestige and limited edition items.
SOLID JASPER Reference: Solid1
Refers to the original white stoneware body which was coloured with the addition of metal oxides. Oxides were added when the body was in a powdered state, the ingredients were then mixed and milled to form a clay body which could then be thrown on a potters wheel, molded, or sculpted.

Pictured: C18th Solid Pale Blue Jasper Sugar Bowl.

DIP JASPER Reference: Dip2
Refers to the process of dipping an object made from solid Jasper or stoneware into Jasper slip. The oxides which were used to give the Jasper body a uniform shade of color were costly and could be difficult to obtain, especially in regard to Cobalt Oxide. It was less expensive to layer slip made with a small amount of oxide, over an object made from solid white Jasper or stoneware, rather than use more of the oxide to tint the entire clay body.

Some early items were made from a coloured Jasper body, but also had Jasper slip applied on top. Eg: Solid Pale Blue Jasper medallions layered with Dark Blue or Black Jasper slip.

Pictured: C20th Sage Green Jasper Dip Sugar Bowl.

TEA WARE Reference: Teaware3
Describes Jasper tea and desert services. The sales catalog for 1787 described tea and desert items as "polished within" - this refers to the fact that early solid Jasper was able to be polished in the lapidary fashion, such was the superior hardness of the solid Jasper body. The polished result was extremely smooth, and had a glossy sheen. As well as using highly decorative bas-reliefs, such as the Arabesque design, teaware also featured lattice and engine-turned decoration.

Also referred to as Cabinet Pieces, due to the high-quality of the craftsmanship these items were more for display than use.

Pictured: C18th Sage Green Jasper Covered Cup.

DICED Reference: Diced4
A pattern in the form of a chequered effect produced on the engine-turning lathe. This chequered or 'diced' appearance is achieved by cutting through the coloured slip on the Jasper surface, through to the contrasting ground (usually white) at regular intervals. Such a pattern appears only on high status Jasper production, and is generally associated with tri-color items.

Also known as Dicing, or Diced Ware.

Pictured: C19th Tri-Color Coffee Can.

STRAP WARE
I know little about this type of Jasper ware. It appears to be a pattern formed over the Jasper body by using thin strips of Jasper applied in a interwoven fashion. Also known as Strap Work.

Contributions would be welcome about this particular ware.

Pictured: Two C18th Strap Ware Examples.

ARABESQUE
A design consisting of intricate interlaced lines, bands, strap work and floral motifs. Originally it was adapted by Islamic craftsmen from Roman sources.

Pictured: A typical Arabesque Design.

ENGINE-TURNING
The engine-turning lathe could create a range of repetitive and highly decortaive finishes on the body of unfired Jasper. A prescion cutting tool achieved this effect by cutting through layers of colored Jasper slip to reveal the contrasting Jasper body beneath. Examples of this included Fluting and Diced decoration.

Pictured: A distinctive pattern achieved by engine-turning.

LATTICE WORK
A fine applied trellis work pattern which appears mostly on Jasper from the late 18th-Century.

Pictured: C18th Custard Cup with Lattice decoration.