Group shows are vulnerable to extremes. They can be substantial or fade around the edges. Naked, at the Jensen Gallery, is one of the most considerable mixed exhibitions we've seen in Auckland for some time. It ranges from a tiny fascinating cult figure from 6000BC and an ancient Greek vase to really big names in contemporary art from overseas matched by work from New Zealand artists.

Opposite the door are two drawings by perpetually controversial British artist Tracey Emin, both fairly slight things but giving a glimpse of the excellence of her drawing. This is reinforced by her animation film on the other side of the partition. Here Emin's shock tactics first hold the viewer in horrid fascination. In agitated animation are two legs in high-heeled shoes and hands busily engaged with herself. Once the viewer is over the initial shock there is the possibility of admiring the way the powerfully descriptive line reinforces the whole jolting experience.

Despite the title of the show and the figurative nature of the work there is little emphasis elsewhere on sex. On the contrary, Marina Abramovic's luminous Nude with Skeleton is a reminder of mortality. A skeleton lies on top of the quietly breathing figure which cradles its bony hand in hers as if "half in love with easeful death". It is truly memorable.

In complete contrast is the witty, silent, black and white film by Carolee Schneemann where, naked, she covers herself with glue and rolls in masses of torn paper. Most amusing of all is when her cat, a feline critic, takes a look at the action and flees.

From there the big names roll out, notably Eric Fischl whose Tumbling Woman in the context of 9/11 is a gripping presentation of a falling body in the moment of death just before it splits and smashes. A typical Fischl hint of ghastly reality is a detail which appallingly suggests absolute terror.

Local artists are less dramatic but the technically superb over-life-size charcoal drawing by Jude Rae of a model standing poised on one leg is an impressive tour de force. A crouching, Rodinesque figure Fallen and a remarkable woodcut, Two Women, announce the arrival of a major talent in Christchurch artist Sam Harrison.

In this fine show the figurative work is counterpointed by some plain, naked abstract painting.

Post Office, the show at Artspace curated by Robyn Pickens, also features international artists, with masses of accompanying text.

Artspace was once a post office and this provides the theme of the exhibition. The idea that places of work like this office and some factories have been converted to art activity is basic to the theme. Fashionably, most of the works are video loops and photographs.

One outstanding piece by German film-maker Harun Farocki traces the manufacture of bricks across a number of cultures. The building blocks are made by hand in traditional ways in some places and by the exactness of modern technology in others. The detail is tellingly selected.

There is the by now obligatory piece that shows the repetitive nature of factory work. Tehching Hsieh speeds up punching a time-clock and produces an endless jiggling motion. A documentary from Syria by Oussama Mohammad features a man out of work who joined the navy and became indoctrinated to the point where he says he would shoot his brother if he criticised the ruling regime.

All this filmed material is accompanied by masses of text. Most of it is tediously obscure whether it is an almost unreadable little book by British artist Liam Gillick or Fiona Jack's conversation with friends about an enlarged photograph of polling in New Plymouth the first time women were allowed to vote. The historic photograph is fascinating; it is pure Deadwood - a frontier town. The intriguing details are a woman driving a horse and trap very fast and a man ducking out of the way. Men crowd the door of the booth. A trio of woman look excluded. Yet the discussion soon departs from the photograph and becomes simply undistinguished chat.

The show has a big theme but makes only insubstantial efforts to really follow it through. More visual energy, less video and fewer texts would have helped.

Painting and sculpture have much more substance. At the Sue Crockford Gallery, Gretchen Albrecht has abandoned the oval and demi-lune shapes she favoured in the past in favour of conventional rectangular canvases. This suits her new subject matter which is still a vortex but no longer the sea or stars but simply roses. These paintings have the swirl and energy and assured brushwork as before but the forms burst outward rather than move in depth.

Two have the instant appeal of rich, rose-red but another which recalls a line from Andrew Marvell, "Annihilating all that's made/ To a green thought in a green shade", evokes all pleasure in all green growth. The other is a black rose, which has a memorial quality. Albrecht's style remains the same but her thinking continues to develop in these impressive works.

Green is the signature colour of the sculpture of Chris Charteris at FHE Galleries. It is the green of pounamu, wonderfully cut, polished to transparency and mounted in light boxes. Treated in this way the stone is singularly beautiful with its veining that resembles the wash and waves of the sea.

One piece, different from the others, shows outwardly the rough grey surface of stone but deep valleys in the shape of a cross reveal the lovely green beneath the surface.

These works are matched on an impressively larger scale by loops of stones rounded by wave action and assembled as huge necklaces and towers. This is a compelling show that is wonderfully indigenous. Everywhere there is truth and beauty revealed in stone.

Leather is the basis of some lively work by Janna van Hasselt at Seed Gallery. She begins with colour lithography and adds painting and line drawing. Very inventively the works often move from twisting line across to wild colour with an intermediary stage of carefully painted plant forms as catalyst for the transition. The result is thoughtful and charming.

What: Naked
Where and when: Jensen Gallery, 11 McColl St, to July 9
TJ says: A splendid show of figurative art by big international names and talented locals.

What: Post Office
Where and when: Artspace, 300 Karangahape Rd, to June 26
TJ says: The theme "work" produces some interesting video film loops and a good deal of inconsequential text as art.

What: Roses in the Snow, by Gretchen Albrecht
Where and when: Sue Crockford Gallery, Endeans Building, 2 Queen St, to June 19
TJ says: The artist's vividly painted vortexes remain but surge out from plain backgrounds to make images that have their beginnings in roses.

What: To the Heart of the Matter, by Chris Charteris
Where and when: FHE Galleries, 2 Kitchener St, to June 12
TJ says: The heart of greenstone made luminous by being cut so thin that light shows through it as part of a masterly exhibition revealing beauty in stone.

What: Pin'n' Mix, by Janna van Hasselt
Where and when: Seed Gallery, 23A Crowhurst St, Newmarket, to June 6
TJ says: A lively show of considerable charm that uses plants as intermediaries between line and colour.

For gallery listings, see www.nzherald.