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Always in your hands
Since 1874. We are a manufacturer of ceramic clays for industry, pottery, and artistic ceramics, and natural modelling clays for crafts, fine arts, and education.
Based in Barcelona (Spain), SIO-2® combines craftsmanship, innovation, and sustainability to create high-quality clays trusted by artists, studios, and professionals worldwide.
Our goal is to innovate with natural materials, developing products that meet the needs of the most demanding users. In every clay we produce, we bring together experience, passion, and precision, caring for every detail, from conception to the final manufacturing process.
Our ISO 9001:2015 certified Quality System ensures continuous improvement, while social responsibility and environmental respect are core values of our company philosophy.
Always in your hands, SIO-2® is your brand.
Why SIO-2®?
More than a company: a commitment
At SIO-2, we believe that a company is defined not only by its results but also by how it contributes to improving the world around it. From the very beginning, we have worked with a clear idea: to create real and lasting value. We know that companies play an important role in society, and we embrace that responsibility with ethics, respect, and common sense.
We believe in truth over appearance, honesty over profit, and that the end never justifies the means. This commitment starts at home, from the shareholders to the entire team, and reaches the last user shaping a piece with SIO-2 clay anywhere in the world. We want every product we make to enhance the experience of those who create with it.
Clay: our reason for being
Clay is often seen simply as “just clay”. At SIO-2, we see it differently: clay is the origin of creativity, the starting point for ceramists and artists. It is their material, their tool and, in a way, their voice.
That is why our priority is to give clay the value it deserves. Each formula begins with a question: “What does the artist need? What is he or she looking for? What does he or she expect from the material?”
But a good formula is not enough. Technical excellence and reproducibility are essential. A product is only excellent if it is reliable, batch after batch. For this reason, we take great care in every step of the process, relying on technology, knowledge and experience.
We also pay close attention to packaging. We know it communicates, too. Each package must reflect the quality, respect, and passion behind it. Like a fine perfume, the exterior matters because it protects something valuable.
Our commitment continues throughout the distribution network. We work with serious companies and professionals who know and appreciate this small but fascinating world of ceramics. We are proud that with many of them we share a relationship that goes beyond business: trust, respect and friendship.
Natural clays for crafts, fine arts and education
The market is full of modeling pastes made from synthetic materials. At SIO-2, we chose another path: staying faithful to the natural character of clay.
Our modeling clays are made with real natural clay. And that makes all the difference: unique plasticity, a fresh touch thanks to the kneading water, and the absence of artificial odors. The result is an authentic modeling experience.
We do not aim to flood the market with yet another product. Our goal is to satisfy those who can appreciate the difference.
In short
SIO-2® is more than a clay brand. It is a way of understanding work, materials, and relationships with people. We believe in the beauty of well-made things, in honesty as a guiding principle, and in clay as a vehicle for creativity, expression and truth.
Choosing SIO-2® is not just choosing a clay: it is sharing a way of seeing and understanding the world.
Our Team
Management Team: Rafael Boixadera (Managing Director), Mari Carmen Ferrer (Technical Director),
Javier Aragón (Operations Director), and Antonio Márquez (Deputy Director & CFO).
Marketing, Sales and Customer Service: Susana Enrich, Thomas Scherl, Núria Lindo and Noelia Mancebo.
Administration and Support: Pilar Cembellín, Martha Martí and Daniel Valls.
Laboratory: Ester Jurado and Pol Navarro.
SIO-2 Store: Marta Nieto, María Maceira, Yailing Bisbal, David Mateu, Marina Carmona, Júlia Novoa and Toni López.
Production and Maintenance
Warehouse and Logistics
Our Story
150 years making clay
The company Cerámica Collet S.A. commemorates the 150th anniversary of the beginning of its activity in 1874, in L'Hospitalet de Llobregat (Barcelona). This story, that of Can Batllori-Cerámica Collet, has lasted to the present day after a century and a half manufacturing clay for ceramics.
The Batllori-Collet family comes from a long line of potters from Sants. In 1874, Mariano Batllori Juvert built a house, a kiln, and a pottery workshop in L'Hospitalet de Llobregat, so that his son, Josep Batllori Munné, could continue the family tradition. However, Josep's premature death in 1895 left the pottery in the hands of his two daughters, still minors. The company was managed by a family council until 1917, when the eldest daughter, Francisca Batllori Saumell, took over the reins of the company.
During the first half of the 20th century, the artisan activity was strengthened by Calixto Collet Collet, Francisca's husband. With a solid artistic training, Calixto drove the company forward with an appreciated production of utilitarian and ornamental ceramics for construction and architecture, which were announced as “Especialitat en tubos de totes dimensions, fets a màquina. Cairons i Trenca-aigües vernissats de varis colors. Tubos patentats, marca “Ideal”, vernissats per dins i fora. Models en terra Cuita, per a la construcció de façanes de totes menes” (Specialty in tubes of all dimensions, made by machine. Tiles and water breakers varnished in various colours. Patented tubes, brand "Ideal", varnished inside and outside. Terracotta models for the construction of facades of all types) (L'Esguard magazine, 1929). “Can Batllori” ceramics became benchmarks in the sector.
When the Spanish Civil War broke out (1936), the company was collectivized. The businessmen were expelled under threats and the workers who were part of the control committees took charge of the activity. Later, the facilities were seized by the Generalitat to manufacture war ammunition. In 1938, the factory caught fire due to a large explosion, and it suffered further damage from the town bombings in 1939. At the end of the war, with the facilities completely destroyed, Calixto Collet obtained the financing needed to rebuild the factory and resume production. After a decade of great difficulties, Can Batllori was able to recover its competitive position in the context of the ceramic factories in the Barcelonès county.
In the 1950s, Rodolfo Collet Batllori, son of Calixto and a great innovator, assumed the leadership of the company and oriented manufacturing towards complementary products for construction, investing in production and logistics processes to meet the needs of Spanish “developmentalism” of the moment. The company was renamed “Cerámica Collet”. In 1965, due to the strong demographic pressure in the surroundings of Barcelona, the manufacture of clay was moved to a new plant in Esparreguera.
Facade of the house and entrance of the Can Batllori factory on the current Enric Prat de la Riba Street 76-82 in L'Hospitalet de Llobregat (1920s).
Clay preparation in settling ponds at the Can Batllori factory
in L'Hospitalet de Llobregat (1920s).
Utilitarian and ornamental ceramics for construction
and architecture from Can Batllori.
Starting in the 1950s, the company oriented manufacturing
towards structural ceramic products.
In the 70s, coinciding with the crisis of ceramic materials for construction, Cerámica Collet's activity took a substantial turn towards the manufacture of ceramic clay bodies, becoming a supplier of quality raw materials for potters and small industries, which allowed them to abandon the artisanal production of clay and concentrate exclusively on their finished ceramics activity. The leadership passed to the brothers Rodolfo and Calixto Collet Ferrer, sons of Rodolfo Collet Batllori, who promote the Esparreguera factory and develop the red clay market in the Iberian Peninsula.
Yet the success of prepared clay did not stop only as a raw material for ceramics. The vision of the Collet brothers led them to invest in a packaging machine for 2 kg clay formats intended for crafts and education. In 1979, the “SIO-2” brand and the first catalogue was born, which had been published in 4 languages: Spanish, French, English and German. That same year, the public limited company Cerámica Collet S.A. was created.
The SIO-2 brand was also extended to ceramic clays and quickly became popular in the industrial and pottery sector of the country. The success of the product and the emergence of new needs led the Collet brothers to develop new formulas and product typologies, including grogged clays for ceramists and sculptors. In 1981, the last batch of ceramic pieces was produced at the L'Hospitalet factory, ending the production activity, and its facilities remained as the company’s offices and warehouse.
In 1984, the first export sales began and the “SIO-2 PLUS” self-hardening clay was presented to the market, which started to be promoted at European fairs. The great demand for both ceramic and modelling clays pushed Cerámica Collet to make big investments in the Esparreguera factory, and the SIO-2 brand also began to be known in Europe.
In 1979, the SIO-2 brand was born
and the first vacuum packaging for clay for crafts.
In 1979, the SIO-2 brand was born
and the first vacuum packaging for clay for crafts.
First SIO-2 catalogs of ceramic clay bodies
for export (80s).
The natural self-hardening clay SIO-2 PLUS is promoted at Spanish and foreign fairs (1992).
In the early 90s, overwhelmed by success and without offspring, the Collet brothers decided to look for external investors to grow and professionalize the company. In 1992, with the entry of new partners, the company gained new momentum. Under the direction of Jaume Casas and the support of Rodolfo and Calixto Collet, the mission of increasing exports was undertaken, beginning a new stage of investment in facilities and human resources. The company reaches the end of the millennium with growth and obtaining ISO 9001 certification for its quality system.
Nonetheless, market trends in the new millennium impacted the company's profits and, in 2002, the shareholders decided to grant the leading of the company to the management team, headed by Rafael Boixadera and Antonio Márquez, to adapt the commercial strategies and both human and material assets to the new needs and demands of the market. In 2003, the offices moved to Esparreguera and marketing and resource optimization strategies were intensified.
In 2005, the company decided to invest in the distribution of ceramic supplies, and so, it acquired a store in La Bisbal d’Empordà, which moved the following year to Vulpellac, under the “Àngela Colls” brand. In 2009 and 2010, new physical stores were opened in Esparreguera and Barcelona, and an online store. The goal was to energize and popularize artistic ceramics, taking advantage of the creative current of the moment.
Starting in 2015, the company experienced a strong growth thanks to the materialization of the efforts and strategies that were initiated years earlier, and, in 2016, the branch Collet Clays Corp. was created, which was dedicated to the import and distribution of SIO-2 ceramic clays in the United States.
Cerámica Collet S.A. reaches its 150th anniversary as a leader in the manufacture of ceramic clays and clays for modelling, with an export level of 70%, and sales in more than 50 countries on five continents. It is the story of a century-old company that has known how to adapt to the needs of the moment and reinvent itself when necessary to prevail from generation to generation. A company with resilience and solid values, which, above all, has succeeded in believing in people.
Headquarters, factory and warehouse of Ceramica Collet in Esparreguera (2015).
First "Àngela Colls" store in Barcelona (2010).
Comprehensive automation of production (2021).
"SIO-2 Store" in Barcelona (2022).