All of these ornaments were made more or less the same way.  Two half blanks, either solid wood or segmented, were joined together with a temporary joint.  The blank was turned to a sphere and then the temporary joint was split apart.  The hemispheres were hollowed, then glued back together.

A six segment ornament from Baltic Birch plywood with the plies arranged tangentially.

A six segment ornament of Baltic Birch plywood with the plies arranged obliquely to the radius.

Solid soft Maple.  The joint is disguised with one of the grooves, which were filled with Bondo and brass filings.

Soft Maple.  The joint is disguised with one of the burned lines.

Soft Maple with red and green copper wire in a faux Celtic knot pattern.

Mahogany with Pewter wire, again in a Celtic knot pattern.  This time the wire is woven instead of cut into segments.

Hard Maple, with red and green acrylic paint.

Soft Maple with lines filled with red dyed plaster.

I called this a Roundel ornament, because the pattern resembles the Roundels that British and French fighter planes used in WWI.  Four segments of Radiata Pine form the base.  The Roundels are Walnut, Holly and Padouk.

An "early" Roundel pattern birch plywood.  Roundels of Walnut and Holly.

The ornament base is Radiata Pine.  The circles are Walnut, with plaster of Paris forming the star.

Soft Maple segments with thick Maple and Walnut veneer.

Maple segments with walnut veneer.

Walnut ornament with pewter wire.  The gaps were deliberate.  Won't do that again.

Soft Maple with woven red and green copper wire.

The reindeer was made from walnut and maple using a bevel sawn technique.  The padouk ring was a thin layer behind the reindeer image.  The body of the ornament was four square staves of radiata pine.

Shooting Star (in more ways than one).  Starting with a base of 4 rectangular radiata pine staves, a layer of 1/16" walnut and maple were added.  Then the star and contrails were cut out of maple and glued on.  A square rectangle of scrap wood was added to create a recess around the maple pieces, and then filled with Bondo colored with black pigment.

The Moon Santa started with four Radiata Pine staves glued into pairs.  One side was trimmed to 1" thickness, and 1/16" layers of walnut and maple glued on.  The pieces of the Santa were cut out of Walnut (background), Padouk (hat), Maple (face), and Holly (tassel, hat trim, beard, mustache, hair) and glued on top of the maple layer.  The deliberate gaps were filled with black tinted Bondo, sort of giving a stained glass effect.

The base is the same as the Moon Santa ornament.  Padouk and Maple were gang sawed with a spiral scroll saw blade which leaves a wide kerf and the pieces glued to the base.  The kerf was filled with black tinted Bondo.

A wider version of the Celtic Knot pattern.  After incising the lines are burned in with a wire.