In the 1970s, Nivola returned to easel painting: a way of thinking about space, reflecting on the relationship between a flat surface and a three-dimensional image. The series of large geometrical figures is characterized by warm and dull tones - in vogue in the 1970s - and by the ambiguity between figure and background: the volume of the figures is denied or accentuated from time to time by the application of the color that passes from one plane to another. 'other. In this case too, the artist's interest is in the definition and perception of space.

In the early 1950s Nivola began to make a series of cut sheet figures, the Ancestors, with a technique partly suggested by the sculpture of his friend Alexander Calder. The first known example, the large female form exhibited here, was made in Sardinia during a trip in 1952. Subsequently, the artist returned to the theme several times, creating among other things in 1957-58 a group of figures as decoration of a department store, Carr's Department Store in West Orange, New Jersey. Placed on the facade of the building, the metal sheets are associated by Nivola with the clamor and animation of commerce and modern life.

In 1954, with the decoration of the Olivetti showroom, opened in the center of New York, on Fifth Avenue, Nivola inaugurated his career as a sculptor for architecture. Designed by the Milanese studio BBPR, the showroom is an environment full of imaginative inventions with a surrealist flavor. Perfect example of "synthesis of the arts" in which architecture, sculpture and design harmoniously contribute to the overall effect, the project has its most striking element in Nivola's work. The relief, 23 meters long, was made with a technique invented by the artist, sandcasting (plaster sculpture from a matrix modeled in the sand), and represents a series of semi-abstract figures, divinities who carry small human figures in their wombs and who they welcome the visitor with broad gestures of welcome. Visually detached from the sea green floor and the sky blue ceiling by means of a line of light, the "sand wall", with its grainy surface reminiscent of the beach, gives an impression of lightness and helps to evoke the image of Mediterranean nature. The great success of the project imposes Nivola in the international field as the ideal collaborator for modernist architects, and at the same time sanctions the overseas affirmation of Italian design and creativity.

The research on space, constant in Nivola's art, led him in the seventies to elaborate the theme of "rooms" in drawings, paintings and sculptures. Completed works rather than models, the rooms rework the idea of the physical and symbolic space of the Gramsci monument at the same time, removing it from the sphere of public art to reinterpret it in a private and existential key. Simple geometric shapes open on the front, the rooms have small windows that let in the light modifying the space.

Starting in 1974, Nivola returned to painting with a series of paintings that revisit the American urban landscape, especially New York (the previous versions of the theme were from the early 1940s). They are works that capture the magical vitality and at the same time the nervous and chaotic quality of the city. "I am determined - he writes - to put everything I know and understand about the subject, the art of painting and the discipline of seeing into a series of paintings. It will be hard work, not joyful work but a sad, objective, truthful approach to a ruthless, realistic city ". Passers-by, cars, the old New York of brick buildings, skyscrapers of glass and steel merge, rendered through a thick and regular sign that becomes almost abstract.

In 1953 Nivola published a series of drawings in Interiors that illustrate the project of the “village-pergola” conceived for his native town, Orani. The artist imagines connecting all the houses through pergolas, transforming the streets into intimate spaces, collectively liveable by the inhabitants; the pergola is a sign that underlines - and in doing so strengthens - the social bond between individuals. Today, the modernity of the idea is striking, which goes beyond sculpture, painting and architecture to go into the terrain of everyday life.

The sandcasting technique invented by Nivola made it possible to create relief panels that could be mounted to cover even very large wall surfaces, such as the facade of the Mutual of Hartford Insurance Company, built in 1958 in Hartford, Connecticut, of which the museum preserves the sketch. The sculptures were made with the same material used for the construction of modern buildings, concrete, and with the same carpentry; transported in the formworks used to build them, they could travel with the normal means of transport used on the site and without special insurance conditions. Nivola aimed at a “normalization” of sculpture, which would deprive it of its aura of exceptionality, bringing it closer to everyday life. The work of art, which has become part of common existence, had to contribute to improving society by creating a more harmonious and pleasant environment.

In his project to transform Orani into a “village-pergola”, Nivola foresees in the center of the main square a monument dedicated to the profession - typical of the village - of the bricklayer, a profession that had belonged to his father and to which he himself had been educated. With the project - never completed - for the monument to the bricklayer of Orani, the series of Building blocks (building blocks) is inaugurated. Inspired by the principles of cubist collage, these are figures composed of interlocking overlapping concrete blocks. Nivola had conceived the Building Blocks as gigantic structures, "as tall as buildings", with which he could fully achieve the fusion of sculpture and architecture. While failing to make them in the expected size, the artist creates several models for the series.

At the beginning of the 1960s, Nivola began to use terracotta to create small-sized works, seen as a totally free form of expression, an alternative to the rigor required by public works, subject to the will of the clients and the need for architecture. Nivola with a few gestures outlines seascapes in which small figures rest on the beach or swim towards the horizon. In the seventies Nivola, disillusioned and disgusted by contemporary society, creates new beds and beaches, humorous and sarcastic, often with an open sexual content, and creates the series of the Piscine, places of urban leisure where bodies are massed and every relationship with the nature is denied or distorted.

The photo of the concrete version of the sculpture is used, in 1958, as an image in the advertising series "Great ideas of Western man" by Container Corporation of America, accompanied by the quote from Seneca "The most powerful is he who has himself on his own power". Over the course of the 1960s, Nivola made several versions of this powerful and geometric figure.

Starting in 1974, Nivola returned to painting with a series of paintings that revisit the American urban landscape, especially New York (the previous versions of the theme were from the early 1940s). They are works that capture the magical vitality and at the same time the nervous and chaotic quality of the city. "I am determined - he writes - to put everything I know and understand about the subject, the art of painting and the discipline of seeing into a series of paintings. It will be hard work, not joyful work but a sad, objective, truthful approach to a ruthless, realistic city ”. Passers-by, cars, the old New York of brick buildings, skyscrapers of glass and steel merge, rendered through a thick and regular sign that becomes almost abstract.

At the beginning of the 1960s, Nivola began to use terracotta to create small-sized works, seen as a totally free form of expression, an alternative to the rigor required by public works, subject to the will of the clients and the need for architecture. Nivola with a few gestures outlines seascapes in which small figures rest on the beach or swim towards the horizon. In the seventies Nivola, disillusioned and disgusted by contemporary society, creates new beds and beaches, humorous and sarcastic, often with an open sexual content, and creates the series of the Piscine, places of urban leisure where bodies are massed and every relationship with the nature is denied or distorted.

At the beginning of the 1960s, Nivola began to use terracotta to create small-sized works, seen as a totally free form of expression, an alternative to the rigor required by public works, subject to the will of the clients and the need for architecture. The Beds, inspired by Etruscan sarcophagi, symbolize, by extension, the totality of man's existence: the life of a couple in all its variations, moments of solitude, happiness and despair. Nivola exhibits them on white bases covered with wheat sprouts, a symbol of rebirth traditionally used in Sardinia in the rites of Holy Week. From the microcosm of the Beds, we pass with the Beaches to the macrocosm of nature: Nivola with a few gestures outlines seascapes in which small figures rest on the beach or swim towards the horizon.

Already at the beginning of the seventies Nivola developed what he called "an appetite for marble and bronze": the desire to use the noble materials of sculpture to approach "pure" art, independent of architecture. “For some time now, a simple, essential force has been increasingly defined in my sculpture. Here spirit and senses collaborate in the commitment to give shape and meaning to the material. There is a feminine form as a result, but not necessarily as a starting point. The pot-bellied wall of the rustic house, in my magical childhood age, always hid a treasure: the flat and thin bread that swells in the heat of the oven, a promise to satisfy the usual hunger. Likewise, the pregnant woman hides the secret of a wonderful child in her womb. " Thus Nivola explains the meaning of the great Mothers - icons of his late maturity.

The theme of widows once again descended from that of argia, but was also linked, more generally, to the idea of the Sardinian woman matured in decades of loving reflection on the subject. "All Sardinian women are widows," Nivola said, "even those who never marry."